Let Tan (a) = 2, then the square of sin a + sin (a) cos (a)=

Let Tan (a) = 2, then the square of sin a + sin (a) cos (a)=

Sina / cosa = 2 sin ^ 2 A / cos ^ 2 a = 4 cos ^ 2 = 1-sin ^ 2 a brings in sin ^ 2 a = 0.8
Then cosa / Sina = 0.5 is multiplied by sin ^ 2 A to get Sina cosa = 0.4, so it is 1.2

Given Tan α = 2, calculate ① 2cos (π 2 + α) − cos (π − α) sin (π 2 − α) − 3sin (π + α) ② SIN3 α − cos α SIN3 α + 2cos α

① ∵ Tan α = 2, ∵ original formula = − 2Sin α + cos α + 3sin α = − 2tan α + 11 + 3tan α = - 37; ② ∵ Tan α = 2, ∵ original formula = SIN3 α − cos (sin2 α + Cos2 α) SIN3 α + 2cos α (sin2 α + Cos2 α) = tan3 α − tan2 α − 1tan3 α + 2tan2 α + 2 = 16