Establish the identity.cos 3x = cos3 x - 3 sin2 x cos x
What will be an ideal response?
cos 3x = cos (2x + x) = cos 2x cos x - sin 2x sin x = (cos2 x - sin2 x) cos x - 2 sin x cos x sin x = cos3 x - sin2 x cos x - 2 sin2 x cos x = cos3 x - 3 sin2 x cos x.
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Establish the identity.(sin x)(tan x cos x - cot x cos x) = 1 - 2 cos 2 x
What will be an ideal response?
Use the Half-angle Formulas to find the exact value of the trigonometric function. tan 165°
A. -2 - 
B. 2 - 
C. 2 + 
D. -2 + 
Complete the identity.
= ?
A. sec2 ? B. 1 C. cot2 ? D. csc2 ?
Who wrote the groundbreaking work On the Origin of Species and is responsible for the birth of the evolutionary perspective?
A. Urie Bronfenbrenner B. Lev Vygotsky C. Charles Darwin D. Konrad Lorenz