Answer:
Step-by-step explanation:
[tex](1 - Cos \ x)*(1+\dfrac{1}{Cos \ x})=(1- Cos \ x)* \left(\dfrac{Cos \x }{Cos \ x}+\dfrac{1}{Cos \ x} \right)[/tex]
[tex]= (1-Cos \ x)*\left(\dfrac{Cos \ x + 1}{Cos x}\right)\\\\=\dfrac{(1-Cos \ x)(1+Cos \ x)}{Cos \ x}=\dfrac{1^{2}-Cos^{2} \ x}{Cos \ x}\\\\=\dfrac{1 -Cos^{2} \ x}{Cos \ x}\\\\=\dfrac{Sin^{2} \ x}{Cos \ x}\\\\=Sin \ x * \dfrac{ Sin \ x}{Cos \ x}\\\\[/tex]
= Sin x * Tan x
Hence proved