precalc question
\[\frac{ \sec \Theta }{ 1-\sin \Theta }= \frac{ 1+\sin \Theta }{ \cos^{3} \Theta }\]
we cannot manipulate the properties of the trig identities so does anyone know how to solve it
Do you want to solve or prove an identity?
prove an identity
cos^2x =1-sin^2 x =(1-sin x)(1+sinx)
but we cannot manipualte identities like i tried multiplying by the conjugate on the left side which gave 1-sin^2theta but we cannot use that to say it equals cos^2 theta
Sec theta = 1/cos theta substitute that for sec theta, and simplify.
yeah our teacher said we cannot manipulate the identity like that
That's not true; you probably misunderstood what your teacher said. sec theta = 1/cos theta, is a reciprocal function property, which is permissable to substitute when proving an identity.
like we have to leave it as sin^2+cos^2=1
he said making it 1-sin^2=cos^2 requires a whole separate proof which we are not allowed to do
There is no way to prove that identity if you do not substitute 1/cos theta for sec theta.
Join our real-time social learning platform and learn together with your friends!