Pythagorean Trigonometry Identities:
sin2θ + cos2 = 1;
tan2θ + 1 = sec2θ;
1 + cot2θ = cosec2θ;
Pythagorean Trigonometry Identities:
sin2θ + cos2 = 1;
tan2θ + 1 = sec2θ;
1 + cot2θ = cosec2θ;
These identities are the trigonometric version of the Pythagorean theorem. Finding the Pythagorean identity is made easier here.