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3 votes
Solve each equation for 0 x 360 sqrt 2 cosx+1=0 please hurry

User Darscan
by
5.1k points

2 Answers

2 votes

Answer:


120\º \text{ and } 240\º

or in radians:


$(2\pi )/(3) \text{ and } (4\pi )/(3)$

Explanation:

From the way you wrote, you want to solve the equation


\sqrt {2 \cos(x)+1}=0 for
0 \leq x < 360\º, or in radians
[0, 2\pi)


\sqrt {2 \cos(x)+1}=0

Square both sides


2 \cos(x) +1= 0


2\cos(x)=-1


$\cos(x)=-(1)/(2) $

In the Unit Circle, considering one revolution (interval
[0, 2\pi)),

the values where
$\cos(x)=-(1)/(2) $ are in Quadrant II and III.

Once


$\cos(x)= (1)/(2) \text{ for } x = 60\º \text{ in the Quadrant I}$

The values where


$\cos(x)=-(1)/(2) $ are 120º and 240º.

User InteXX
by
4.3k points
4 votes

Answer:

C on edge

Explanation:

User Wassim Sboui
by
4.9k points