Prove the Identity $(\tan x+1)^{2}=\frac{1+2 \sin x \cos x}{\cos ^{2} x}$

question 17

Essay

Prove the identity:
$(\tan x+1)^{2}=\frac{1+2 \sin x \cos x}{\cos ^{2} x}$

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Definitions:

Humerus

The humerus is the long bone in the upper arm, extending from the shoulder to the elbow.

Tibia

A large bone located in the lower leg, between the knee and the ankle, parallel to the fibula.

Ulna

One of the two long bones in the forearm, located on the side opposite the thumb and running parallel to the radius.

Appendicular Skeleton

Part of the skeleton that includes the bones of the limbs and girdles, facilitating movement.