Thursday

August 21, 2014

August 21, 2014

Posted by **kathleen** on Monday, December 6, 2010 at 3:50pm.

- Math -
**Reiny**, Monday, December 6, 2010 at 4:51pmremember that sin 2x = 2sinxcosx

so 4sinxcosx = 1

2(2sinxcosx) = 1

2(sin2x) = 1

sin2x = 1/2

I will assume you are working in degrees, we can always switch later on

so 2x = 30° or 2x = 150° because of the CAST rule

x = 15° or x = 75°

the period of sin 2x is 180°, so adding 180 to any answer will produce new answers

x = 15°, 195°, ...

or

x = 75°, 255°, ...

In Radians:

15° = π/12 radians

x = π/12, 13π/12....

x = 5π/12, 17π/12, ...

**Related Questions**

Precalculus - I've tried many times to get the equation to balance using trig ...

math - sin2x-cotx = -cotxcos2x Using the various trigonometric identities(i.e. ...

Math 2nd question - Express as a single sine or cosine function (note: this is ...

Math Word Problem - As payment for his daughters yard work, a father agrees to ...

math,help - i am stuck with this problem: Problem #12 Solve by using the ...

math - 1. 4x^2-13x=12 I need to solve this problem by factoring or using the ...

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

Calculus - Solve the first-order initial value problem using half angle formulas...

pre-calc helpppp - Simplify the expression by using a Double-Angle Formula or a ...

Pre-Calc Help!!! - Simplify the expression by using a Double-Angle Formula or a ...