trig
posted by Bob .
To the nearest degree, all of the following angles are solutions of the equation 2sin x + 4 cos 2x =3 except:
(1) 40 degrees
(2) 150 degrees
(3) 166 degrees
(4) 194 degrees

trig 
Reiny
I don't know if you are supposed to do this by simply substiting, or actually solve the equation.
I will solve it
2sinx + 4cos 2x = 3
2sinx + 4(1  2sin^2 x) 3=0
2sinx + 4 8sin^2 x  3 = 0
8sin^2 x  2sinx 1 = 0
sinx = (2 ± √36)/16 = 1/2 or 1/4
x = 30° or 150° or x = 194.4775..° or 345.522°
so to the nearest degree I got
x = 30, 150, 194 and 346
I see only two of these in your list, so the others don't work
Respond to this Question
Similar Questions

Pre Cal
2cos 4theta + 1 = 0 i know how to find the degrees (the last step of the problem), but i don't know how to start the problem. Could someone please show me the steps? 
Trig(continued)
2)Find the solution of sin2 theta = cos theta if 0 < theta < 180 A)30 degrees and 90 degrees B)30 degrees and 150 degrees C)30 degrees, 90 degrees, 150 degrees D)0 degrees, 90 degrees, and 150 degrees sin2 theta = cos theta … 
Math
How do you express in terms of angles less than 90 degrees? 
trig
How do you express in terms of angles less than 90 degrees? 
trigonometry (please double check this)
Solve the following trig equations. give all the positive values of the angle between 0 degrees and 360 degrees that will satisfy each. give any approximate value to the nearest minute only. 1. sin2ƒÆ = (sqrt 3)/2 2. sin^2ƒÆ = … 
Math
One angle of an isosceles triangle is 28°. What are the other 2 angles? 
Math
Find the approximate number of radians, to the nearest hundreth, in the angles with the following dergree measures. a) 60 degrees b) 128.5 degrees c) 150 degrees d) 80 degrees e) 145 degrees f) 325 degrees g) 56.4 degrees h) 230 degrees … 
Trigonometry
Solve the equation cos^2A = sin^2A + sinA when 0¨¬¡A¡360¨¬. Select all the solutions from the list below. A. 330 degrees B. 270 degrees C. 150 degrees D. 30 degrees 
precalculus
Which of the following is NOT a solution to cos^2x=3sin^2x? 
math
connexus com/content/media/64275621201225329PM831257193.png 1) Name a pair of complementary angles. <1 and <4 <1 and <6 <3 and <4 <4 and <5 2) If m<1=43 degrees, what is m<4?