Question

Find sin thita=m+n by 2
$\sqrt{mn}$
Into sec thita

Answer 1

Hi ,

Here I am using A instead of theta.

SinA = ( m + n ) / ( 2√mn )

Cos² A = 1 - sin² A

= 1 - [ ( m+n ) / ( 2√mn ) ]²

= 1 - [ ( m + n )² / 4mn ]

= [ 4mn - ( m + n )² ] / 4mn

= { - [ ( m + n )² - 4mn ] }/ 4mn

= [ - ( m - n )² ] / 4mn

CosA= ( m - n )/2×√ [ -1 / mn]

SecA = 1/cosA

= 2√ (-mn ) / ( m - n )

I hope this helps you.

: )