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Precalculus

# Key Equations

PrecalculusKey Equations

### Key Equations

 arc length $s=rθ s=rθ$ area of a sector $A= 1 2 θ r 2 A= 1 2 θ r 2$ angular speed $ω= θ t ω= θ t$ linear speed $v= s t v= s t$ linear speed related to angular speed $v=rω v=rω$
 Cosine $cost=x cost=x$ Sine $sint=y sint=y$ Pythagorean Identity $cos 2 t+ sin 2 t=1 cos 2 t+ sin 2 t=1$
 Tangent function $tant= sint cost tant= sint cost$ Secant function $sect= 1 cost sect= 1 cost$ Cosecant function $csct= 1 sint csct= 1 sint$ Cotangent function $cott= 1 tant = cost sint cott= 1 tant = cost sint$
 Cofunction Identities $cost=sin( π 2 −t ) sint=cos( π 2 −t ) tant=cot( π 2 −t ) cott=tan( π 2 −t ) sect=csc( π 2 −t ) csct=sec( π 2 −t ) cost=sin( π 2 −t ) sint=cos( π 2 −t ) tant=cot( π 2 −t ) cott=tan( π 2 −t ) sect=csc( π 2 −t ) csct=sec( π 2 −t )$
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