SOLUTION: Solve the equation sin^2x = 3cos^2x. The value of x that satisfies the equation if x lies in the second quadrant is ?°. a. 60° b. 120° c. 150° d. 240° e. 300°

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: Solve the equation sin^2x = 3cos^2x. The value of x that satisfies the equation if x lies in the second quadrant is ?°. a. 60° b. 120° c. 150° d. 240° e. 300°       Log On


   

Question 1170449: Solve the equation sin^2x = 3cos^2x.
The value of x that satisfies the equation if x lies in the second quadrant is
?°.
a. 60°
b. 120°
c. 150°
d. 240°
e. 300°
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the equation sin^2(x) = 3cos^2(x)
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Use parentheses.
sin^2(x) = 3cos^2(x)
1 - cos^2(x) = 3cos^2(x)
4cos^2(x) = 1
cos^2(x) = 1/4
cos(x) = -1/2, +1/2
etc
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Another method
sin^2(x)/cos^2(x) = 3
tan^2(x) = 3
tan(x) = -sqrt(3), +sqrt(3)