Question

Sederhanakan bentuk2 trigonometri
A.cos (90 derajat - \alpha ) / sin (90 derajat -\alpha )

B,tan (90 derajat -\alpha) / sec (90 derajat -\alpha)

Answer 1

Mengenal:
cos(90-a) = sin a
sin(90-a) = cos a
tan(90-a) = cot a
sec(90-a) = cosec a
Sehingga,

a.)
= cos(90-a) / sin(90-a)
= sin a/cos a
= tan a

b.)
= tan(90-a) / sec(90-a)
= cot a / cosec a
= (cos a/sin a) / (1/sin a)
= cos a : sin a x sin a
= cos a

Answer 2

A. cos (90'-α) / sin (90'-α)
    = sin α / cos α
    = tan α

B. tan (90'-α) / sec (90'-α)
   = cot α /  csc α
   = cos α