NapkinCalc

Precalculus — Functions

Function notation

f(x) = x² − 3x defines the machine; f(4) runs it. The definition below is a real function — every cell after it can call it.

f(x)=x2−3⋅xf\left(x\right) = x^{2} - 3 \cdot x define the machine
ya=f(4)y_{a} = \mathrm{f}\left(4\right) = 44 run it: 16 − 12
yb=f(−1)y_{b} = \mathrm{f}\left(-1\right) = 44 negative inputs are fine: 1 + 3