What makes a sequence arithmetic?

Each term differs from the previous one by a constant amount, called the common difference.

Arithmetic Sequence Calculator

Calculate the nth term and the sum of the first n terms of an arithmetic sequence given the first term and common difference.

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Formula

aₙ = a₁ + (n−1)d, Sₙ = (n/2)(2a₁ + (n−1)d)

Trapezoid Area and Number Sequences Explained

The trapezoid area formula and the arithmetic vs. geometric sequence formulas, worked through with real examples.

Geometric Sequence Calculator

Find the nth term and sum of a geometric sequence.

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Calculate the percentage increase or decrease between two values.

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Solve ax² + bx + c = 0 for real roots using the quadratic formula.

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Calculate the average of up to 10 numbers.

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Calculate the population standard deviation of up to 5 numbers.