Posted by **hayden** on Sunday, February 22, 2009 at 8:18pm.

cos^2 (a+x) -sin^2 a=cos x * cos(2a+x)

- precalc and trig -
**Reiny**, Sunday, February 22, 2009 at 8:22pm
see

http://www.jiskha.com/display.cgi?id=1235346549

don't tell my I did all that work, and you didn't even look at it.

- precalc and trig -
**hayden**, Sunday, February 22, 2009 at 8:43pm
i posted a sorry. i posted this twice on that one. And i don't understand how RS=LS and thanks

## Answer This Question

## Related Questions

- TRIG! - Posted by hayden on Monday, February 23, 2009 at 4:05pm. sin^6 x + cos^6...
- trig - Reduce the following to the sine or cosine of one angle: (i) sin145*cos75...
- Mathematics - Trigonometric Identities - Let y represent theta Prove: 1 + 1/tan^...
- tigonometry - expres the following as sums and differences of sines or cosines ...
- Precal - I do not understand how to do this problem ((sin^3 A + cos^3 A)/(sin A...
- Trig - Given: cos u = 3/5; 0 < u < pi/2 cos v = 5/13; 3pi/2 < v < ...
- Trig - Find sin(s+t) and (s-t) if cos(s)= 1/5 and sin(t) = 3/5 and s and t are ...
- Math - Calculus - The identity below is significant because it relates 3 ...
- algebra - Can someone please help me do this problem? That would be great! ...
- calculus - Differentiate. y= (cos x)^x u= cos x du= -sin x dx ln y = ln(cos x)^x...

More Related Questions