Question

Can anyone help solve and explain this?

Solve:

Answer 1

Here's the answer to number 5:

Use the sum/difference formulas to expand

`cos(pi/6)cosx + sin(pi/6)sinx + (cos(pi/6)cosx - sin(pi/6)sinx) = sqrt(3)cosx`

`2cos(pi/6)cosx = sqrt(3)cosx`

`2(sqrt(3)/2cosx) = sqrt(3)cosx`

`sqrt(3)cosx = sqrt(3)cosx`

As required.
Hopefully this helps!