Page 13 - Math SL HB Sem 2
P. 13

The chain rule


                    If g is differentiable  at the point x and f is differentiable  at the point g(x), then the
                    composition fo-c is differentiable  at the point  & moreovsr if
                       y =f(e@) and u:s(t)
                    then y=(u)  and
                          dy   dy d"
                          dt   du dx

                    Example:
                     Iff6l  :  *n nd g(x)  :  a2 + Jx then
                          :
                    f(g(x)  f(x'!+],;r)  = -r' + 3:)  r

                       Example  :

                        Differentiate  the following

                                      4
                        a)    '    Jt-zx

                        b)    y:  G Qx+     1)3
                                   l+3:r
                        c)     v
                                   -r2 +l
                        d)     y=4tun)  ox)
                                    I  Itl  .){
                        e)

                                       I
                        .fi    ,t--
                                   ^l2e-'+l
                                           _r
                               ;r:In              l
                        E)            (;r+2[.r-3)
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