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Derivative Calculator

Find the derivative of any polynomial function with step-by-step power rule application.

Want to solve ANY math problem? Just take a screenshot.

Math.Photos handles algebra, calculus, geometry, statistics, and more — all from a photo or your handwritten notes.

20 free solves · no credit card · no account needed to start

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Find f'(x)

f(x) = (polynomial, e.g. 3x^4 + 2x^3 - 5x^2 + 7x - 1)

How It Works

The Power Rule

The most fundamental derivative rule: d/dx [xⁿ] = n·xⁿ⁻¹. Multiply by the exponent, then reduce the exponent by 1. This works for any real exponent.

Constant Rule

The derivative of any constant is 0. Constants don't change, so their rate of change is zero.

Sum/Difference Rule

The derivative of a sum (or difference) equals the sum (or difference) of derivatives. This lets us differentiate term by term.

Why Derivatives Matter

Derivatives measure rates of change. They're used in physics (velocity, acceleration), economics (marginal cost), and everywhere optimization is needed.

Already did the work? Get it checked instead.

A calculator gives you an answer. It doesn't tell you which line of your working went wrong. Photograph your own steps — handwritten notebook, whiteboard, or a screenshot of an online assignment — and Math.Photos checks them line by line, then points at the exact step where the sign flipped.

Reads handwriting

Photo of your notebook, not a retyped expression.

Step-level verdict

"Line 3 dropped a negative", not just "wrong".

Teach Me mode

Questions that lead you to the fix, not the answer.

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