Math

QuestionProve that 1cos2xsec2x1=1sin2x\frac{1-\cos ^{2} x}{\sec ^{2} x-1} = 1-\sin ^{2} x.

Studdy Solution

STEP 1

Assumptions1. We are given the trigonometric identity 1cosxsecx11sinx\frac{1-\cos ^{} x}{\sec ^{} x-1} \equiv1-\sin ^{} x. . We know the Pythagorean identity sinx+cosx=1\sin^x + \cos^x =1.
3. We know the reciprocal identity secx=1cosx\sec x = \frac{1}{\cos x}.

STEP 2

We begin by simplifying the left side of the equation. We can rewrite sec2x\sec^2x as 1cos2x\frac{1}{\cos^2x}.
1cos2x1cos2x1\frac{1-\cos ^{2} x}{\frac{1}{\cos^2x}-1}

STEP 3

Next, we multiply the numerator and the denominator of the fraction by cos2x\cos^2x to get rid of the fraction in the denominator.
(1cos2x)cos2x1cos2x\frac{(1-\cos ^{2} x)\cos^2x}{1-\cos^2x}

STEP 4

implify the expression. The (1cos2x)(1-\cos^2x) terms cancel out in the numerator and the denominator.
cos2x\cos^2x

STEP 5

We know from the Pythagorean identity that cos2x=1sin2x\cos^2x =1 - \sin^2x.
1sin2x1 - \sin^2xThis is the same as the right side of the original equation, so the identity is verified.
1sin2x1sin2x1 - \sin^2x \equiv1 - \sin^2x

Was this helpful?

Studdy solves anything!

banner

Start learning now

Download Studdy AI Tutor now. Learn with ease and get all help you need to be successful at school.

ParentsInfluencer programContactPolicyTerms
TwitterInstagramFacebookTikTokDiscord