Question

In ∆ABC, angle B = 90°and tanA = 1, then show that the 2sinA. cosA=1

Answer 1

Heya Frnd.........☺

Since TanA = 1

So,

A = 45° ..........(Tan45 = 1)

NOW,

$2 \sin(a) \times \cos(a)$

$= > \: 2 \sin(45) \times \cos(45)$

$= > \: 2 \: (\frac{1}{ \sqrt{2} } ) \times \frac{1}{ \sqrt{2} }$

$= > \: 2( \frac{1}{2} )$

$= > \: 1 \: ............hence \: proved$

_______☺☺☺________

$HOPE \: IT \: WILL \: HELP \: U ........$

Answer 2

look at the picture....