Tuesday

January 27, 2015

January 27, 2015

Posted by **rick** on Tuesday, February 26, 2008 at 1:26pm.

sin (3 pi/2 + x) + sin (3 pi/2 -x) = -2 cos x

- trig -
**drwls**, Tuesday, February 26, 2008 at 5:47pmUse the identities

sin (a + b) = sin a cos b + sin b cos a

sin (a - b) = sin a cos b - sin b cos a

and the facts that sin 3 pi/2 = -1 and cos 3 pi/2 = 0

**Answer this Question**

**Related Questions**

Math - Calculus - The identity below is significant because it relates 3 ...

TRIG! - Posted by hayden on Monday, February 23, 2009 at 4:05pm. sin^6 x + cos^6...

Mathematics - Trigonometric Identities - Let y represent theta Prove: 1 + 1/tan^...

Trigonometry - Prove the identity sin(x+y+z)+sin(x+y-z)+sin(x-y+z)+ sin(x-y-z...

MathsSs triG - Consider sin(x-360)sin(90-x)tan(-x)/cos(90+x) 1.A.SIMPLIFY sin(x-...

trig - it says to verify the following identity, working only on one side: cotx+...

trig - Reduce the following to the sine or cosine of one angle: (i) sin145*cos75...

tigonometry - expres the following as sums and differences of sines or cosines ...

Trigonometry desperate help, clueless girl here - 2. solve cos 2x-3sin x cos 2x...

Trigonometry - 1.Solve tan^2x + tan x – 1 = 0 for the principal value(s) to two ...