関連ワード:  antiderivative of 2e^t    antiderivative of 2e^x    integral of 2e t    integral of 2e to the x    integral of 2e t 2    integral of 2e t dt    antiderivative of 1/2e^t    integral of t 2e 2t    integral of t^2e^-3t    integral of t 2e tdt