How do you verify the identity #sec^2thetasin^2theta=sec^4theta-(tan^4theta+sec^2theta)#? Trigonometry Trigonometric Identities and Equations Proving Identities 1 Answer Bdub Oct 7, 2016 see below Explanation: #sec^2 theta sin^2 theta= sec^4 theta-(tan^4 theta + sec^2 theta)# Right Side :#=sec^4 theta-(tan^2 thetatan^2theta+sec^2theta)# #=sec^4 theta-((sec^2-1)(sec^2theta-1) + sec^2theta)# #=sec^4 theta-(sec^4theta-2sec^2theta+1+sec^2theta)# #=sec^4 theta-(sec^4theta-sec^2theta+1)# #=sec^4 theta-sec^4theta+sec^2theta-1# #=sec^2 theta-1# #=tan^2 theta# #=sin^2 theta/cos^2 theta# #=1/cos^2 theta sin^2theta# #=sec^2 theta sin^2 theta# #:.=# Left Side Answer link Related questions What does it mean to prove a trigonometric identity? How do you prove #\csc \theta \times \tan \theta = \sec \theta#? How do you prove #(1-\cos^2 x)(1+\cot^2 x) = 1#? How do you show that #2 \sin x \cos x = \sin 2x#? is true for #(5pi)/6#? How do you prove that #sec xcot x = csc x#? How do you prove that #cos 2x(1 + tan 2x) = 1#? How do you prove that #(2sinx)/[secx(cos4x-sin4x)]=tan2x#? How do you verify the identity: #-cotx =(sin3x+sinx)/(cos3x-cosx)#? How do you prove that #(tanx+cosx)/(1+sinx)=secx#? How do you prove the identity #(sinx - cosx)/(sinx + cosx) = (2sin^2x-1)/(1+2sinxcosx)#? See all questions in Proving Identities Impact of this question 1835 views around the world You can reuse this answer Creative Commons License