Yes it is true:
(1 - cos^2 x) = sin^2 x Sqr.(1 - cos^2 x) = sin x and (-sinx) True, since sin x negative. Also, x terminates in quadrant 3 and 4. Hope this is helpful
Fraction? They are already decimals
Sus subsistíais ve. D s s d d s d f
5*3= 15
3*15=15
15/3=5
15/5=3
