Question

Упростите: (sina+cosa)^2-1-sin2a

Answer 1

=sin²α+2sinαcosα+cos²α-1-2sinαcosα=(sin²α+cos²α=1)=1-1=0

Answer 2

sin²a+2sinacosa+cos²a-sin²a-cos²a-2sinacosa=0

Answer 3

Спасибо.