Question

sin(180-(a+b)) what is it's value​

Answer 1

Hello Mate,

Here is your answer,

Let's take

$a + b = \alpha \\ \\ so \\ \\ \sin( 180 - (a + b) ) \\ \\ = \sin(180 - \alpha ) \\ \\ (180 - \alpha) \: \: \: lies \: in \: the \: second \: \\ quadrant \: where \: sine \: and \: cosecant \\ are \: positive \: only \\ \\ \\ so \\ \\ \\ \sin(180 - \alpha ) \\ \\ = sin (\alpha) \\ \\ we \: know \: \: \alpha = a + b \\ \\ so \: the \: required \: answer \: is \\ \\ \sin(a + b)$

Hope it helps:)