Let g (x) = 2x sin x . (a) Find g′(x) . (b) Find the gradient of the graph of g at x = π .
a) f'(x)=uv'+vu' if f(x)= uv
u=2x u'=2 v=sin(x) v'=cos(x)
g'(x)=2x cos(x) +2sin(x)
b) g'(π) = 2π cos(π)+2sin(π) = 2 π (-1) + 2 (0)
g'(π) = -2π
a) f'(x)=uv'+vu' if f(x)= uv
u=2x u'=2 v=sin(x) v'=cos(x)
g'(x)=2x cos(x) +2sin(x)
b) g'(π) = 2π cos(π)+2sin(π) = 2 π (-1) + 2 (0)
g'(π) = -2π
