Question

please help me to prove this.

Answer 1

hope it helped u .. there are many more way to solve this qstn .. but I solved it like this ...
:)

Answer 2

heya...!!!

we know that:-

π = 180

AND,

sin²∅ + cos²∅ = 1


NOW,


cos ²π/4 + sin²(π - π/4) + sin²5π/4 + sin²(π + 3π/4)

=> (cos²π/4 + sin²π/4) + sin²(π/2 + 3π/4) + sin²3π/4

=> 1 + (cos²3π/4 + sin²3π/4)

=> 1 + 1 = 2