Answer:
Note that the three identities above all involve squaring and the number 1.You can see the Pythagorean-Theorom relationship clearly if you consider the unit circle, where the angle is t, the "opposite" side is sin(t) = y, the "adjacent" side is cos(t) = x, and the hypotenuse is 1.. We have additional identities related to the functional status of the trig ratios:
Explanation: