CalculusAntiderivative
posted by Max .
Solve the following initial value problem:
dr/dt=7cos(pi(t)), r(1/4)=14
r(t)=?

dr/dt = 7cos πt
r = 7/π sin πt + c
14 = 7/π sin π/4 + c
14 = 7/(π√2) + c
c = 14  7/(π√2)
r = 7/π sin πt + 14  7/(π√2)