関連ワード:  e x is exponential function    e^x is exponential function or not    e to the power x is exponential function    e^x is exponential function or algebraic function    is y e x an exponential function    is f x )= e x an exponential function    exponential function fx e x is    is e raised to x an exponential function    e in exponential functions    what does e mean in exponential functions