Wednesday

April 16, 2014

April 16, 2014

Posted by **Devon** on Monday, April 16, 2007 at 9:14pm.

2cos^2x+3sinx=0

the way it stands, that is a "nasty" question.

Are you sure the second term isn't 2sin(2x) ?

no, its as i wrote it.

then it's got me stymied, I must be missing something rather obvious, sorry!

thanks for trying!

2cos^2x+3sinx=0

2-2sin^2x + 3 sinx=0

sin^2 x - 3/2 sin x - 1=0

quadratic equation..

sinx= (3/2 +-sqrt(9/4 +4) /2

sinx= 3/4 +- 5/4

sin x= -1/2 works.

check me.

thank you!

**Related Questions**

trig - how can i find all the exact solutions to the equation : 2cos^2x + 3sinx...

math - the problem is 2cos^2x + sinx-1=0 the directions are to "use an identity ...

help, bobpursely - Please take a look at DEVON's trig equation at 9:14 I must be...

Math - Solving Trig Equations - Solve each equation for 0 is less than and equal...

math - how would you find the angle to (3)^.5sin(2x)-2cos(2x)+2sin^2(x)=1 I know...

Precalculus - Verify the identities. Cos^2x - sin^2x = 2cos^2x - 1 When ...

Math, derivatives - f(x) = x² + 2Cos²x, find f ' (x) a) 2(x+cos x) b) x - sin x ...

trig - 2sin(x)cos(x)+cos(x)=0 I'm looking for exact value solutions in [0, 3&#...

Pre-calc/Calc - Which expression is equivalent to sin(3x) + sin x? A. 2cos(2x)...

equations trig - 2cos^2x-3sinx=0