solve it

solve and post a solution soon..

#Dheeraj

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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
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`\boxed{123}`	$\boxed{123}$

Comments

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).

Mehul Chaturvedi - 6 years, 8 months ago

$Yess.. option is \boxed{a}$

Mehul Chaturvedi - 6 years, 8 months ago

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

Piyush Maheshwari - 6 years, 7 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$