Monday
April 21, 2014

Homework Help: trig

Posted by paul c on Friday, November 24, 2006 at 1:46pm.

express 20sin theta + 4 cos theta as R sin(theta + alpha)

R sin(theta + alpha) =
R cos(alpha)sin(theta) +
R sin(alpha)cos(theta)

---->

Rcos(alpha) = 20

Rsin(alpha) = 4

The x-y coordinates of a point on a circle of radius R that makes an angle og alpha with the positive x-axis are with radius R are R cos(alpha) and R sin(alpha) respectively.

R follows from:

20^2 + 4^2 = R^2

If you divide the two equations you get tan(alpha)

Answer this Question

First Name:
School Subject:
Answer:

Related Questions

Calculus - I wanted to confirm that I solved these problems correctly (we had to...
Pre Calc. - Use the sum or difference identity to find the exact value of sin255...
Maths: Partial Differentiation - 1) If x = rcos theta and y = r sin theta, show ...
Algebra II - Multiple Choice Which expression is NOT equivalent to 1? (theta) ...
trigonometry - can you correct the rest for me please? Express each as a ...
trigonometry - can you correct the rest for me please? Express each as a ...
trigonomtry - can you correct the rest for me please? Express each as a function...
Trig - Which expression equivalent to: cos(theta + pi/2). A)cos theta B)-cos ...
Algebra II - Which of the following expressions are not equal to 1? A) sin^2 ...
algebra - Can someone please help me do this problem? That would be great! ...

Search
Members