New user? Sign up

Existing user? Log in

solve and post a solution soon..

Note by Dheeraj Agarwal 3 years, 9 months ago

Easy Math Editor

*italics*

_italics_

**bold**

__bold__

- bulleted- list

1. numbered2. list

paragraph 1paragraph 2

paragraph 1

paragraph 2

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

> This is a quote

This is a quote

# I indented these lines # 4 spaces, and now they show # up as a code block. print "hello world"

2 \times 3

2^{34}

a_{i-1}

\frac{2}{3}

\sqrt{2}

\sum_{i=1}^3

\sin \theta

\boxed{123}

Sort by:

Yesss...., I also got it!!

Log in to reply

\(Yess.. option is \boxed{a}\)

We know, tan(90) = [ tan(70) + tan(20) ] / [ 1 - tan(70).tan(20) ]. Therefore, 1 - tan(70).tan(20) = 0 So, tan(70).tan(20) = 1 ...(A)

Expanding tan(70) = [ tan(50) + tan(20) ] / [ 1- tan(50).tan(20) ]. Therefore, tan(50) + tan(20) = tan(70) * [ 1- tan(50).tan(20) ]. that is, tan(50) + tan(20) = tan(70) - tan(70).tan(50).tan(20). that is, 2.tan(50) + tan(20) = tan(50) + tan(70) - tan(70)tan(50).tan(20). = tan(50) + tan(70) - tan(50) ....[ from equation (A) ] = tan(70).

Problem Loading...

Note Loading...

Set Loading...

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

Sort by:

TopNewestYesss...., I also got it!!

Log in to reply

\(Yess.. option is \boxed{a}\)

Log in to reply

We know, tan(90) = [ tan(70) + tan(20) ] / [ 1 - tan(70).tan(20) ]. Therefore, 1 - tan(70).tan(20) = 0 So, tan(70).tan(20) = 1 ...(A)

Expanding tan(70) = [ tan(50) + tan(20) ] / [ 1- tan(50).tan(20) ]. Therefore, tan(50) + tan(20) = tan(70) * [ 1- tan(50).tan(20) ]. that is, tan(50) + tan(20) = tan(70) - tan(70).tan(50).tan(20). that is, 2.tan(50) + tan(20) = tan(50) + tan(70) - tan(70)tan(50).tan(20). = tan(50) + tan(70) - tan(50) ....[ from equation (A) ] = tan(70).

Log in to reply