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MrK's Simplified Maths
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Welcome to MrK's Simplified Maths!

Here, we make mathematics simple, engaging, and fun for students of all levels. Whether you're in primary school, high school, or just looking to brush up on your math skills, this channel is for you! 📚

We cover everything from basic maths concepts to more advanced topics like algebra, geometry, calculus, and beyond. Each video breaks down complex ideas into easy-to-follow lessons, with step-by-step explanations, real-life examples, and helpful tips to improve your problem-solving skills.

Join us on this journey to master mathematics and discover the beauty of numbers. Don't forget to subscribe and hit the notification bell for regular updates! 🔔✏️

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Unable to parse item

Invidious encountered an error while trying to parse this item. For more information see below:

Show technical details 
Title: `Missing hash key: "collectionThumbnailViewModel" (KeyError)`
Date: `2026-07-13T19:09:55Z`
Route: `/channel/UC7uZoF-dJacezLFdRXkffjA`
Version: `2026.02.07-118d635 @ (HEAD detached at v2.20260207.0)`

<details>
<summary>Backtrace</summary>
<p>
   
```
Missing hash key: "collectionThumbnailViewModel" (KeyError)
  from /usr/share/crystal/src/hash.cr:1198:9 in '??'
  from /usr/share/crystal/src/json/any.cr:149:5 in 'process'
  from src/invidious/yt_backend/extractors.cr:524:17 in 'process'
  from src/invidious/yt_backend/extractors.cr:1035:17 in 'parse_item'
  from src/invidious/yt_backend/extractors.cr:1082:14 in 'extract_items'
  from src/invidious/channels/videos.cr:29:22 in 'get_60_videos:continuation:sort_by'
  from src/invidious/routes/channels.cr:56:36 in 'videos'
  from lib/kemal/src/kemal/route.cr:13:9 in '->'
  from src/invidious/helpers/handlers.cr:31:37 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from lib/kemal/src/kemal/filter_handler.cr:22:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/invidious/helpers/handlers.cr:80:12 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/ext/kemal_static_file_handler.cr:127:14 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/request_processor.cr:51:11 in 'handle_client'
  from /usr/share/crystal/src/fiber.cr:170:11 in 'run'
  from ???
```
</p>
</details>

Unable to parse item

Invidious encountered an error while trying to parse this item. For more information see below:

Show technical details 
Title: `Missing hash key: "collectionThumbnailViewModel" (KeyError)`
Date: `2026-07-13T19:09:55Z`
Route: `/channel/UC7uZoF-dJacezLFdRXkffjA`
Version: `2026.02.07-118d635 @ (HEAD detached at v2.20260207.0)`

<details>
<summary>Backtrace</summary>
<p>
   
```
Missing hash key: "collectionThumbnailViewModel" (KeyError)
  from /usr/share/crystal/src/hash.cr:1198:9 in '??'
  from /usr/share/crystal/src/json/any.cr:149:5 in 'process'
  from src/invidious/yt_backend/extractors.cr:524:17 in 'process'
  from src/invidious/yt_backend/extractors.cr:1035:17 in 'parse_item'
  from src/invidious/yt_backend/extractors.cr:1082:14 in 'extract_items'
  from src/invidious/channels/videos.cr:29:22 in 'get_60_videos:continuation:sort_by'
  from src/invidious/routes/channels.cr:56:36 in 'videos'
  from lib/kemal/src/kemal/route.cr:13:9 in '->'
  from src/invidious/helpers/handlers.cr:31:37 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from lib/kemal/src/kemal/filter_handler.cr:22:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/invidious/helpers/handlers.cr:80:12 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/ext/kemal_static_file_handler.cr:127:14 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/request_processor.cr:51:11 in 'handle_client'
  from /usr/share/crystal/src/fiber.cr:170:11 in 'run'
  from ???
```
</p>
</details>

Unable to parse item

Invidious encountered an error while trying to parse this item. For more information see below:

Show technical details 
Title: `Missing hash key: "collectionThumbnailViewModel" (KeyError)`
Date: `2026-07-13T19:09:55Z`
Route: `/channel/UC7uZoF-dJacezLFdRXkffjA`
Version: `2026.02.07-118d635 @ (HEAD detached at v2.20260207.0)`

<details>
<summary>Backtrace</summary>
<p>
   
```
Missing hash key: "collectionThumbnailViewModel" (KeyError)
  from /usr/share/crystal/src/hash.cr:1198:9 in '??'
  from /usr/share/crystal/src/json/any.cr:149:5 in 'process'
  from src/invidious/yt_backend/extractors.cr:524:17 in 'process'
  from src/invidious/yt_backend/extractors.cr:1035:17 in 'parse_item'
  from src/invidious/yt_backend/extractors.cr:1082:14 in 'extract_items'
  from src/invidious/channels/videos.cr:29:22 in 'get_60_videos:continuation:sort_by'
  from src/invidious/routes/channels.cr:56:36 in 'videos'
  from lib/kemal/src/kemal/route.cr:13:9 in '->'
  from src/invidious/helpers/handlers.cr:31:37 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from lib/kemal/src/kemal/filter_handler.cr:22:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/invidious/helpers/handlers.cr:80:12 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/ext/kemal_static_file_handler.cr:127:14 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/request_processor.cr:51:11 in 'handle_client'
  from /usr/share/crystal/src/fiber.cr:170:11 in 'run'
  from ???
```
</p>
</details>

Unable to parse item

Invidious encountered an error while trying to parse this item. For more information see below:

Show technical details 
Title: `Missing hash key: "collectionThumbnailViewModel" (KeyError)`
Date: `2026-07-13T19:09:55Z`
Route: `/channel/UC7uZoF-dJacezLFdRXkffjA`
Version: `2026.02.07-118d635 @ (HEAD detached at v2.20260207.0)`

<details>
<summary>Backtrace</summary>
<p>
   
```
Missing hash key: "collectionThumbnailViewModel" (KeyError)
  from /usr/share/crystal/src/hash.cr:1198:9 in '??'
  from /usr/share/crystal/src/json/any.cr:149:5 in 'process'
  from src/invidious/yt_backend/extractors.cr:524:17 in 'process'
  from src/invidious/yt_backend/extractors.cr:1035:17 in 'parse_item'
  from src/invidious/yt_backend/extractors.cr:1082:14 in 'extract_items'
  from src/invidious/channels/videos.cr:29:22 in 'get_60_videos:continuation:sort_by'
  from src/invidious/routes/channels.cr:56:36 in 'videos'
  from lib/kemal/src/kemal/route.cr:13:9 in '->'
  from src/invidious/helpers/handlers.cr:31:37 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from lib/kemal/src/kemal/filter_handler.cr:22:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/invidious/helpers/handlers.cr:80:12 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/ext/kemal_static_file_handler.cr:127:14 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/request_processor.cr:51:11 in 'handle_client'
  from /usr/share/crystal/src/fiber.cr:170:11 in 'run'
  from ???
```
</p>
</details>

Unable to parse item

Invidious encountered an error while trying to parse this item. For more information see below:

Show technical details 
Title: `Missing hash key: "collectionThumbnailViewModel" (KeyError)`
Date: `2026-07-13T19:09:55Z`
Route: `/channel/UC7uZoF-dJacezLFdRXkffjA`
Version: `2026.02.07-118d635 @ (HEAD detached at v2.20260207.0)`

<details>
<summary>Backtrace</summary>
<p>
   
```
Missing hash key: "collectionThumbnailViewModel" (KeyError)
  from /usr/share/crystal/src/hash.cr:1198:9 in '??'
  from /usr/share/crystal/src/json/any.cr:149:5 in 'process'
  from src/invidious/yt_backend/extractors.cr:524:17 in 'process'
  from src/invidious/yt_backend/extractors.cr:1035:17 in 'parse_item'
  from src/invidious/yt_backend/extractors.cr:1082:14 in 'extract_items'
  from src/invidious/channels/videos.cr:29:22 in 'get_60_videos:continuation:sort_by'
  from src/invidious/routes/channels.cr:56:36 in 'videos'
  from lib/kemal/src/kemal/route.cr:13:9 in '->'
  from src/invidious/helpers/handlers.cr:31:37 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from lib/kemal/src/kemal/filter_handler.cr:22:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/invidious/helpers/handlers.cr:80:12 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/ext/kemal_static_file_handler.cr:127:14 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/request_processor.cr:51:11 in 'handle_client'
  from /usr/share/crystal/src/fiber.cr:170:11 in 'run'
  from ???
```
</p>
</details>

Unable to parse item

Invidious encountered an error while trying to parse this item. For more information see below:

Show technical details 
Title: `Missing hash key: "collectionThumbnailViewModel" (KeyError)`
Date: `2026-07-13T19:09:55Z`
Route: `/channel/UC7uZoF-dJacezLFdRXkffjA`
Version: `2026.02.07-118d635 @ (HEAD detached at v2.20260207.0)`

<details>
<summary>Backtrace</summary>
<p>
   
```
Missing hash key: "collectionThumbnailViewModel" (KeyError)
  from /usr/share/crystal/src/hash.cr:1198:9 in '??'
  from /usr/share/crystal/src/json/any.cr:149:5 in 'process'
  from src/invidious/yt_backend/extractors.cr:524:17 in 'process'
  from src/invidious/yt_backend/extractors.cr:1035:17 in 'parse_item'
  from src/invidious/yt_backend/extractors.cr:1082:14 in 'extract_items'
  from src/invidious/channels/videos.cr:29:22 in 'get_60_videos:continuation:sort_by'
  from src/invidious/routes/channels.cr:56:36 in 'videos'
  from lib/kemal/src/kemal/route.cr:13:9 in '->'
  from src/invidious/helpers/handlers.cr:31:37 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from lib/kemal/src/kemal/filter_handler.cr:22:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/invidious/helpers/handlers.cr:80:12 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/ext/kemal_static_file_handler.cr:127:14 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/request_processor.cr:51:11 in 'handle_client'
  from /usr/share/crystal/src/fiber.cr:170:11 in 'run'
  from ???
```
</p>
</details>

Unable to parse item

Invidious encountered an error while trying to parse this item. For more information see below:

Show technical details 
Title: `Missing hash key: "collectionThumbnailViewModel" (KeyError)`
Date: `2026-07-13T19:09:55Z`
Route: `/channel/UC7uZoF-dJacezLFdRXkffjA`
Version: `2026.02.07-118d635 @ (HEAD detached at v2.20260207.0)`

<details>
<summary>Backtrace</summary>
<p>
   
```
Missing hash key: "collectionThumbnailViewModel" (KeyError)
  from /usr/share/crystal/src/hash.cr:1198:9 in '??'
  from /usr/share/crystal/src/json/any.cr:149:5 in 'process'
  from src/invidious/yt_backend/extractors.cr:524:17 in 'process'
  from src/invidious/yt_backend/extractors.cr:1035:17 in 'parse_item'
  from src/invidious/yt_backend/extractors.cr:1082:14 in 'extract_items'
  from src/invidious/channels/videos.cr:29:22 in 'get_60_videos:continuation:sort_by'
  from src/invidious/routes/channels.cr:56:36 in 'videos'
  from lib/kemal/src/kemal/route.cr:13:9 in '->'
  from src/invidious/helpers/handlers.cr:31:37 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from lib/kemal/src/kemal/filter_handler.cr:22:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/invidious/helpers/handlers.cr:80:12 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/ext/kemal_static_file_handler.cr:127:14 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/request_processor.cr:51:11 in 'handle_client'
  from /usr/share/crystal/src/fiber.cr:170:11 in 'run'
  from ???
```
</p>
</details>

Unable to parse item

Invidious encountered an error while trying to parse this item. For more information see below:

Show technical details 
Title: `Missing hash key: "collectionThumbnailViewModel" (KeyError)`
Date: `2026-07-13T19:09:55Z`
Route: `/channel/UC7uZoF-dJacezLFdRXkffjA`
Version: `2026.02.07-118d635 @ (HEAD detached at v2.20260207.0)`

<details>
<summary>Backtrace</summary>
<p>
   
```
Missing hash key: "collectionThumbnailViewModel" (KeyError)
  from /usr/share/crystal/src/hash.cr:1198:9 in '??'
  from /usr/share/crystal/src/json/any.cr:149:5 in 'process'
  from src/invidious/yt_backend/extractors.cr:524:17 in 'process'
  from src/invidious/yt_backend/extractors.cr:1035:17 in 'parse_item'
  from src/invidious/yt_backend/extractors.cr:1082:14 in 'extract_items'
  from src/invidious/channels/videos.cr:29:22 in 'get_60_videos:continuation:sort_by'
  from src/invidious/routes/channels.cr:56:36 in 'videos'
  from lib/kemal/src/kemal/route.cr:13:9 in '->'
  from src/invidious/helpers/handlers.cr:31:37 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from lib/kemal/src/kemal/filter_handler.cr:22:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/invidious/helpers/handlers.cr:80:12 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call_next'
  from src/ext/kemal_static_file_handler.cr:127:14 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/handler.cr:30:7 in 'call'
  from /usr/share/crystal/src/http/server/request_processor.cr:51:11 in 'handle_client'
  from /usr/share/crystal/src/fiber.cr:170:11 in 'run'
  from ???
```
</p>
</details>