Question

If sin 0 + 2cos 0= 1, prove that cos 0- 2 sin 0 = 2​

Answer 1

Answer:

sinA +2cosA =1.

by square, both sides.

sin²A +4cos²A +4 sinA. cosA=1

1-cos²A +4 -4 sin²A +4 sinA. cosA =1

cos²A+2sin²A- 4 sinA. cosA=4

(cosA-2sinA) ²=2²

cosA-2sinA=2

proved.