## Excel in math and science

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Easy Math Editor

`*italics*`

or`_italics_`

italics`**bold**`

or`__bold__`

boldNote: you must add a full line of space before and after lists for them to show up correctlyparagraph 1

paragraph 2

`[example link](https://brilliant.org)`

`> This is a quote`

Remember to wrap math in \( ... \) or \[ ... \] to ensure proper formatting.`2 \times 3`

`2^{34}`

`a_{i-1}`

`\frac{2}{3}`

`\sqrt{2}`

`\sum_{i=1}^3`

`\sin \theta`

`\boxed{123}`

## Comments

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\(L.H.S=l(\sin(\theta)\cos(\phi)+\sin(\phi)\cos(\theta))=l \left(\dfrac{BC \cdot n}{l^2}+\dfrac{m \cdot DC}{l^2}\right)=\dfrac 1 l \left(BC \cdot n+DC \cdot m \right)\).

\(R.H.S= n \cdot \dfrac{BC}{l}+m \cdot \dfrac{CD}{l}=\dfrac 1 l \left(BC \cdot n+DC \cdot m \right)\).

\(L.H.S=R.H.S\). Proved.

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But it's not given that \(AC\) is a diameter right?

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I guess we have to assume that it is.

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