Question

Solve this equation on the interval 0 θ < 2π. If there is only one solution, write it in the first box and write NONE in the second box. If there is no solution, write NONE in both boxes.

Round your answer(s) to two decimal places using radians.
-2 cos(θ) + 1 = 2

θ = (smaller value of θ)
θ = (larger value of θ)

Answer 1

the interval is 0( which is less than or equal to) theta ( which is less than) 2pi

Answer 2

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

the related angle is cos inverse of 1/2 , which is 60 degrees

Answer 3

cos is negative in the 2 and 3 quadrants

Answer 4

x= 180 -60 and x= 180 + 60

x= 120 , 240 degrees

Answer 5

\[\frac{2\pi}{3} , \frac{4\pi}{3} \] in radians

Answer 6

thanks. but the answer seems to be wrong? not sure why

Answer 7

I am fairly sure what I did was correct

Answer 8

could it be because the question says round the answer to two decimal points in radians?

Answer 9

yes lol :|

Answer 10

obviously if you entered the exact values then they wouldnt like it

Answer 11

I assumed you would know how to convert the exact values into radians, lol, just calculator work

Answer 12

yes, however i dont have a calc lol! i think the first one is 2(3.14)/3 ?

Answer 13

http://www.wolframalpha.com/input/?i=cos%28x%29+%3D-1%2F2+%2C+0%3Cx%3C360

theres a calculator

even solves eqns and integrals and everything

Answer 14

I use it to check my answers

Answer 15

ok thanks. but to be 100% sure(kind of forgot) radians is using pi as 3.14?

Answer 16

yes approx that ,

Answer 17

thanks mate. got it right!

Answer 18

would you also be able to show me how to do the question just above this question?