Question

-1+sina.cosa/tana=-sin square a

Answer 1

hey there! it would be better if u send a pic of this question.

Answer 2

Hi------------------=
we know tana=sina/cosa
put in your equation
-1+sinacosa/sina/cosa
-1+sinacos^2a/sina
-1+cos^2a
now we know that
sin^2a+cos^2a=1
put in your equation
-(sin^2a+cos^2a)+cos^2a
-sin^2a
it this your answer
hope it help