Abstract: A powertrain for transmitting power to a driven wheel of a motor vehicle includes a power source that includes a reversible electric machine. A first transmission includes an input driveably connected to the power source, a first output, and a mechanism for producing a stepless variable range of ratios of a speed of the output to a speed of the input. An epicyclic transmission includes a second input driveably connected to the power source, a third input driveably connected to the first output, and a second output driveably connected to a drive wheel. The transmissions produce a range of speed of the drive wheel that varies from negative to positive and includes zero.