Posted by bandit5571 on Tuesday, January 11, 2011 at 11:02pm.
solve the equation
1+4sin(x)=4cos^2(x)

pre calc  bandit5571, Tuesday, January 11, 2011 at 11:05pm
without a graphing utility

pre calc  Reiny, Wednesday, January 12, 2011 at 12:08am
1+4sin(x)=4cos^2(x)
1+4sinx = 4(1  sin^2 x)
4sin^2 x + 4sinx 3 = 0
(2sinx  1)(2sinx + 3) = 0
sinx = 1/2 or sinx = 3/2
the last part is not possible since sinx is between 1 and +1
so sinx = 1/2
x must be in quadrants I or II
I know sin 30° = 1/2
so x = 30° or 150°
in radians
x = π/6 or x = 5π/6
Answer This Question
Related Questions
 Trigonometry  Solve the equation for solutions in the interval 0<=theta<...
 trig  Write an equation for simple harmonic motion, given that the amplitude ...
 PRE CALC PLEASE HELP!!!!!!!!  find the solutions of the equation that are in ...
 pre cal 2  solve the equation 4cos^2x1=0
 Math: Parametric Equations  The graph of the parametric equations x=cos(t) y=...
 PreCalculus  Solve the equation 4sin x = e^x on the interval (0, 1). Correctly...
 Calc III  Express the volume of the solid that the cylinder r = 4cos(theta) ...
 Math  (34sin^2A)(13tan^2A) =(3tan^2A)(4cos^A3)
 trig  cos@4SIN@=1 then sin@+4cos@=
 PreCal  Hi, can someone please solve this stepbystep for me? I really don't ...
More Related Questions