Question

How do you evaluate this `sqrt2-2sqrt2sin^2 15pi/4` ?

Answer 1

`0`

Explanation:

`\sqrt2-2\sqrt2\sin^2({15\pi}/4)`

`=\sqrt2-2\sqrt2\sin^2(4\pi-{\pi}/4)`

`=\sqrt2-2\sqrt2(1/\sqrt2)^2`

`=\sqrt2-2\sqrt2(1/2)`

`=\sqrt2-\sqrt2`

`=0`