(fg)′ = f′g + fg′

Product Rule Calculator

Free online product rule calculator. Differentiate products with step-by-step solutions that show both terms — no signup, no Pro wall.

Product examples ready Steps labeled No signup

Steps free — no Pro wall Works offline in your browser

What the product rule says

You cannot differentiate a product by multiplying the separate derivatives alone. The correct identity is (fg)′ = f′g + fg′. A product rule calculator expands both terms and labels the rule so you can check each half of your written solution.

Always write both factors before differentiating. A common error is computing only f′g and forgetting fg′ when one factor “looks easy.”

How to use this product rule derivative calculator

  1. Enter a product with * between factors (e.g. x^2*sin(x)).
  2. Press Calculate and locate the product-rule step.
  3. Verify each factor’s derivative, including any chain-rule pieces.
  4. Compare the simplified sum with your homework answer.

Product rule practice set

  • x^2*sin(x) — polynomial times trig
  • x*e^x — classic textbook product
  • x*ln(x) — product with a log
  • sin(x)*cos(x) — two trig factors
  • x^3*e^(2*x) — product plus chain on the exponential
  • (x+1)*sqrt(x) — linear times root

Products nested with other rules

When a factor is a quotient or a composition, the step list stacks rules: product on the outside, chain or quotient inside. For pure quotients, prefer the quotient rule calculator. For pure compositions, use the chain rule calculator.

Evaluating the derivative afterward at a number? Continue with the derivative at a point calculator workflow after you trust f′(x).

Product rule calculator FAQ

What is the product rule?

(fg)′ = f′g + fg′ — differentiate one factor at a time and add.

How do I use this calculator?

Enter a product, Calculate, and read the labeled product-rule steps under the result.

Is it free?

Yes — free steps with no account.

What if a factor needs the chain rule?

The engine applies chain inside the product terms. Try x*sin(x^2).

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