trig
posted by ashley  HELP PLEASEE!!! .
3sin(2x)2cos(x)=0

Use the equation
sin(2x) = 2 sin x cos x
so that
6 sinx cosx 2 cosx = 0
cosx*(1  3sinx) = 0
(I divided out 2)
So the equation is satisfied wherever cosx = 0 or sinx = 1/3
x = pi/2 and 0.3398 radians are two solutions. There are others in other quadrants.
Respond to this Question
Similar Questions

Math  Trig Substitution
How can I solve the integral of x^3√(9x^2) dx using trigonometric substitution? 
Calculus
Find the derivative of y with respect to x: y=3sin^4(2x)^1 y=[3sin(2x)^1]^4 y'=4[3sin(2x)^1]^3 (3cos(2x)^1)(1) (2x)^2 y'=[12cos(2x)^1][3sin^3(2x)^1][2x]^2 but the answer does not have a 3 in front of sin. What happened … 
trig
finding the equivalent polar equation 2x+3y=6 I got r=6/2cos(theta)3sin(theta) can anyone check plz 
Calc
How do you know what shape the graph in the xyplane represented by x=3sin(t) and y=2cos(t) is? 
Math
Can you help me with this? I did this many times and got different answers each time. Find f. f ''(x) = 3e^x + 3sin(x) f(0) = 0 f(π) = 0 My work: f ''(x) = 3e^x + 3sin(t) f'(x) = 3e^x  3cos(t) + C f(x) = 3e^x 3sin(t) + Cx + 
trig
Find minimum value of 2cos x + 2cos y 
trig
Find minimum value of 2cos x + 2cos y 
trig
Find minimum value of 2cos x + 2cos y 
trigonometry
Find all solutions on the interval [0.2pi) A) 3sin(t)=15cos(t)sin(t) I have no clue... b) 8cos^2(t)=32cos(t) All i did was move around the equation to make an quadratic for B. so 8cos^2(t)2cos(t)+3 = 0 
Mathematics
Given that 2cos^2 x  3sin x 3 = 0, show that 2sin^2 x + 3sin x +1 = 0?