Question

Помогите пожалуйста!

Answer 1

1) (sina/cosa +cosa/sina)(1-cos^2a)=

((sin^2a+cos^2)/(sina*cosa*))*sin^2a=1/cosa*sina=tga

4) (sin^3a +sin^2a * cosa + cos^3a + cos^2a * sina= sin^3a + cosa - cos^3a +cos^3a +sina - sin^3a = cosa + sina

3) 1/(1+tg a) + 1/(1 + ctg a) = 1/(1/cos^2 a) + 1/(1/sin^2 a) = cos^2 a + sin^2 a = 1

Answer 2

1) (sina/cosa +cosa/sina)(1-cos^2a)= ((sin^2a+cos^2)/(sina*cosa*))*sin^2a=1/cosa*sina=tga

2) напиши четче

3) 1+tg^2a = 1/cos^2a, 1+ctg^2a=1/sin^2a => sin^2a +cos^2a = 1

4) (sin^3a +sin^2a * cosa + cos^3a + cos^2a * sina= sin^3a + cosa - cos^3a +cos^3a +sina - sin^3a = cosa + sina