Mark M. answered 02/22/23
Retired math prof. Calc 1, 2 and AP Calculus tutoring experience.
Let f(x) = cos(2x) + 3x - 4
f is continuous on the interval [0, π]
f(0) < 0 and f(π) > 0
So, by the IVT, f(c) = 0 for some number c between 0 and π
cos(2c) + 3c - 4 = 0
So, cos(2c) = 4 - 3c
Do the other problems in a similar manner.