# pre cal 2

posted by .

solve the equation 4cos^2x-1=0

• pre cal 2 -

4c0s^2x - 1 = 0.
4cos^2x = 1,
Divide both sids by 4:
cos^2x = 0.25,
Take sqrt of both sides:
cosx = 0.5,
X = 60 deg.

## Similar Questions

1. ### pre-cal

What are the steps for solving this? Directions Use the quadratic formula to solve the equation in the interval [0,2PI). Then use a graphing utility to approximate the angle x. 4cos^2x-4cosx-1=0 thanks.
2. ### Pre-Cal

Hi, can someone please solve this step-by-step for me?
3. ### pre-cal

solve this system of equation 3x-y+5z-2w=-44 x+6y+4z-w=1 5x-y+z+3w=-15 4y-z-8w=58
4. ### pre calc

solve the equation 1+4sin(x)=4cos^2(x)
5. ### PRE CALCULUS

8-12SIN^2X=4COS^2X SOLVE FOR X
6. ### pre-cal

solve the equation algebraically. 7e^x=11-e^-x
7. ### pre cal verifying identities

how do I verify?? sin(x)+cos3(x)=sin(x)-3cos(x)+4cos^(3)x
8. ### Pre-Cal

Solve the equation for the indicated variable: (ax+b)/(cx+d)=6 , Solve for X
9. ### Pre-cal

Solving the principle values of x of the equation 4cos^2x-3=0
10. ### pre cal

Use factoring to solve the polynomial equation: HINT: Try multiplying each side of the equation by a number to eliminate the denominators. x2/162 + X/18 + 1/9 =0

More Similar Questions