Question

Question #40bb3

Answer 1

see below

Explanation:

Use the following Composite Argument Properties
`color(red)(cos(A-B)=cos A cos B+sinA sinB`
`color(red)(sin(A+B)=sinAcosB+cos A sin B`

Left Hand Side:

`color(green)(cos(pi-theta)+sin(pi/2+ theta)=color(blue)(cos picos theta+sin pi sin theta+sin (pi/2) cos theta+cos (pi/2)sin theta`

`color(blue)(=-1*cos theta+0*sin theta+1*cos theta+0*sin theta`

`color(blue)(=-cos theta+cos theta)`

`color(blue)(=0)`

`color(blue)( :.=` Right Hand Side