Question

Prove the identity sinx=cos(pi/2-x)?

Answer 1

`"see explanation"`

Explanation:

`"using the "color(blue)"trigonometric identity"`

`•color(white)(x)cos(a-b)=cosacosb+sinasinb`

`"here "a=pi/2" and "b=x`

`rArrcos(pi/2-x)`

`=cos(pi/2)cosx+sin(pi/2)sinx`

`=(0xxcosx)+(1xxsinx)=sinx`