How do you solve without a calculator tan squared theta plus 1?

Answer 1

This is the same as secant squared theta [sec²(Θ)].

• Take the identity sin²(Θ) + cos²(Θ) = 1
• Divide both sides by cos²(Θ):

1. sin²(Θ) / cos²(Θ) = tan²(Θ)
2. cos²(Θ) / cos²(Θ) = 1
3. 1 / cos²(Θ) = sec²(Θ)

tan²(Θ) + 1 = sec²(Θ)