conclusion about roots for positive derivative of a polynomial

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If the derivative of a polynomial is always positive then what can we conclude about the number of real roots the original polynomial?

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If the derivative is always positive, then it's never zero. That means there are no turning or stationary points of the original polynomial function. That means it's always increasing (since the derivative is always positive). Since the leading coefficient has to be positive (as it's increasing), you can sketch the curve as an increasing function starting in quadrant 3 for highly negative x and going on to quadrant 1 for highly positive x, and cutting the x-axis exactly once. This means there will be exactly 1 real root.