## haileyy0401 How do you simplify an trigonometric equation like the following? one year ago one year ago

1. haileyy0401

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2. hubertH

u need ur identities, from s$\sin^2+\cos ^2=1$ make sin the subject of the formula

3. hubertH

$\frac{ \sin ^2\theta }{ 1-\cos \theta } =\frac{ 1-\cos ^2\theta }{ 1-\cos \theta } =\frac{( 1-\cos \theta)(1+\cos \theta) }{ (1-\cos \theta) }$

4. haileyy0401

How do you get sin theta squared is equal to (1-cos)(1+cos)?

5. hubertH

do u know this identity?$\sin ^2\theta+\cos ^2\theta=1$

6. haileyy0401

yes.

7. hubertH

now try make sin^2 the subvject of the formula what do u get?

8. hubertH

u'll get a difference of two squares which i'm sure u can solve

9. haileyy0401

you would get sin^2 theta= 1-cos^2 theta?

10. hubertH

yes can u now see that 1- cos^2 theta is a fifference of two squares?

11. hubertH

1-cos^2=(1-cos)(1+cos)