Rewrite as .
Apply the distributive property.
Apply the distributive property.
Apply the distributive property.
Simplify each term.
Multiply by .
Multiply by .
Multiply by .
Multiply .
Raise to the power of .
Raise to the power of .
Use the power rule to combine exponents.
Add and .
Add and .
Simplify (1+tan(x))^2