27Using the Quadratic Equation to Solve Trigonometric Equations You can’t mix trigonometric functions. (Only one trigonometric function at a time!)Must still follow the same basic format:ax2 + bx + c = 02 cos2x + 6 cos x – 4 = 07 tan2x + 10 = 0
36Using Reciprocal Identities to Solve Trigonometric Equations Our calculators don’t have reciprocal function (sec x, csc x, cot x) keys.We can use the reciprocal identities to rewrite secant, cosecant, and cotangent in terms of cosine, sine, and tangent!
39Your Turn:Use the reciprocal identities to solve for solutions algebraically:1. cot x = –102. tan x sec x + 3 tan x = 03. cos x csc x = 2 cos x
40Using Pythagorean Identities to Solve Trigonometric Equations You can use a Pythagorean identity to solve a trigonometric equation when:One of the trig functions is squaredYou can’t factor out a GCFUsing a Pythagorean identity helps you rewrite the squared trig function in terms of the other trig function in the equation