Plot a function to sanity-check homework or data
Type the expression and see the curve — quicker than a graphing calculator when you just need the shape.
Tools used in this guide
The job
Before solving for roots or checking an answer, seeing y = f(x) often tells you everything: where it crosses zero, where it blows up, where it flattens.
Expression, range, plot
Type the function in x — like x^2 - 3*x + 2 or sin(x)/x — set the x range, and plot. Drag to pan; gaps in the curve mark where the function is undefined or off-scale.
- Multiplication needs an explicit *: write 2*x, not 2x.
- Angles are in radians — degrees give misleading trig curves here.
Reading the result
Roots show as x-axis crossings; a parabola x²−3x+2 crosses at 1 and 2, matching the factored form. For numbers rather than the picture, evaluate the same expression in the scientific calculator.