Solve the following trigonometric equation for 7 <= x <= 9: 4cos(3x-20)=1
4*cos(3x - 20) = 1
cos(3x - 20) = 1/4
arccos(1/4) = 3x - 20
Can you take it from here?
=^._.^=
4cos(3x-20=1
cos(3x-20)=1/4
arccos(1/4)=3x-20
1.318116072 = 3x-20
1.318116072+20 = 3x
1.318116072+20/3 = x
21.31811607/3 = x
x = 7.106
Did I do it right?
Yay. :))
Nice job.