Question

(sec x + tan x)²=1+sin x/1-sin x

Answer 1

Sec =1/cos
tan = sin/cos
sec+tan = (1+sin)/cos
(sec+tan)²=(1+sin)²/cos²
cos²=1-sin²=(1-sin)(1+sin)

(1+sin)²/cos²=(1+sin)/(1-sin)

jadi

(sec+tan)²=(1+sin)/(1-sin)
(1+sin)/(1-sin)=(1+sin)/(1-sin)
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