Friday

August 1, 2014

August 1, 2014

Posted by **Jon** on Sunday, November 4, 2012 at 8:08pm.

- Pre-calculas Math -
**Sanya**, Sunday, November 4, 2012 at 9:04pm9pi/12 should be converted into degrees. The value of pi is 180 so all you do is 180 times 9 divided by 12 and then take the cosine of that value.

- Pre-calculas Math -
**Steve**, Monday, November 5, 2012 at 1:53amcosx cosy + sinx siny = cos(x-y)

so, what we have here is

cos(9π/12 - 5π/12) = cos(4π/12) = cos π/3 = 1/2

**Related Questions**

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

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

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

algebra - Can someone please help me do this problem? That would be great! ...

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

MATH - 1.)Find the exact solution algebriacally, if possible: (PLEASE SHOW ALL ...

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

pre-cal - Simplify the given expression........? (2sin2x)(cos6x) sin 2x and cos ...

Calculus 12th grade (double check my work please) - 1.)Find dy/dx when y= Ln (...

Trig - Given: cos u = 3/5; 0 < u < pi/2 cos v = 5/13; 3pi/2 < v < ...