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4 votes
Solve each equation for 0 degrees < x < 360 degrees.

Sqrt 2 cos x + 1 = 0

A.45,315
B.115,245
C.135,225
D.46, 314

Please Help ASAP!

2 Answers

3 votes

Answer:It C

Explanation:

3pi/4 = 135 , 5pi/4 += 225

User ChuckieDub
by
5.0k points
5 votes

Answer:

120 degrees and 330 degrees

Explanation:

Solve each equation for 0 degrees < x < 360 degrees.

Sqrt 2 cos x + 1 = 0

A.45,315

B.115,245

C.135,225

D.46, 314

Please Help ASAP!

Given the expression √(2cosx+1) = 0

Square both sides of the equation;

√(2cosx+1) = 0

2cosx + 1 = 0

2cosx = -1

cos x = -1/2

x = cos^-1(-1/2)

x = -60 degrees

Since cos is negative in the 2nd and 3rd quadrant then;

x = 180-60 = 120 degrees (2nd quadrant)

x = 270+60 = 330 degrees (3rd quadrant)

User Jloriente
by
5.5k points