NapkinCalc

Algebra 2

Quadratics & the discriminant, exponentials & logarithms, and the sums of sequences — verified live.

Lines bend. This course is about the curves that show up everywhere — parabolas (anything thrown), exponentials (anything that grows by a percentage), and the sums hiding inside repeated patterns.

  1. 01 Quadratics & the discriminant A quadratic ax² + bx + c = 0 has its whole personality in one number, the discriminant b² − 4ac: positive → two real roots (the parabola crosses the axis…
  2. 02 Exponentials & logarithms Exponential growth multiplies by the same factor every period — and the logarithm asks the reverse question: how many periods to reach a target? They are the…
  3. 03 Sequences & series Adding 1 + 2 + ⋯ + n one at a time is work; pairing first with last is insight — every pair sums to n + 1, and there are n/2 pairs. The check makes the engine…

next course: Trigonometry →