How do you use the fundamental identities to prove other identities? Trigonometry Trigonometric Identities and Equations Fundamental Identities 1 Answer Kevin B. Feb 22, 2015 Divide the fundamental identity sin^2x + cos^2x = 1sin2x+cos2x=1 by sin^2xsin2x or cos^2xcos2x to derive the other two: sin^2x/sin^2x + cos^2x/sin^2x = 1/sin^2xsin2xsin2x+cos2xsin2x=1sin2x 1 + cot^2x = csc^2x1+cot2x=csc2x sin^2x/cos^2x + cos^2x/cos^2x = 1/cos^2xsin2xcos2x+cos2xcos2x=1cos2x tan^2x + 1 = sec^2xtan2x+1=sec2x Answer link Related questions How do you use the fundamental trigonometric identities to determine the simplified form of the... How do you apply the fundamental identities to values of thetaθ and show that they are true? What are even and odd functions? Is sine, cosine, tangent functions odd or even? How do you simplify sec xcos (frac{\pi}{2} - x )secxcos(π2−x)? If csc z = \frac{17}{8}cscz=178 and cos z= - \frac{15}{17}cosz=−1517, then how do you find cot zcotz? How do you simplify \frac{\sin^4 \theta - \cos^4 \theta}{\sin^2 \theta - \cos^2 \theta} sin4θ−cos4θsin2θ−cos2θ using... How do you prove that tangent is an odd function? How do you prove that sec(pi/3)tan(pi/3)=2sqrt(3)sec(π3)tan(π3)=2√3? How do you simplify (cos4x-cos2x)/(sin 4x + sin 2x)cos4x−cos2xsin4x+sin2x? See all questions in Fundamental Identities Impact of this question 11160 views around the world You can reuse this answer Creative Commons License