Question

1
)
A
(D) 225
If cos-lx - cos-1 Y = a. Then 4x2 - 4xy cos a + y2 is equal to-
(A) 2 sin 2a
(C) 4 sind a
(D) - 4 sin
(B) 4​

Answer 1

Answer:

i could not understand this please rescan your question