Differential calculus

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The graph o a function, drawn in black, an a tangent line tae that function, drawn in reid. The slope o the tangent line equals the derivative o the function at the marked pynt.

In mathematics, differential calculus is a subfield o calculus concerned wi the study o the rates at which quantities chynge. It is ane o the twa tradeetional diveesions o calculus, the ither bein integral calculus.