Name: Rain Xia Student Number: 59118159
Use the function, derivative and second derivative to sketch the graph of f(x) =x^x
f(x)=x^x domain: x≥0. intercepts: when x=0, y=1, therefore the intercept is (0,1). asymptotes: lim x->∞f(x)=∞ lim x->0 f(x)=1
f'(x)=(x^x)(1+lnx) intervals of increase and decrease: when (x^x)(1+lnx)<0.368, the function decreases, when (x^x)(1+lnx)>0.368, the function increases. extrema: f'(x)=(x^x)(1+lnx)=0 when x=0.368, therefore the extrema for f(x) is x=0.368 and it is the global minimum of the funtion.
f”(x)=x^x*[(lnx+1)²+1/x] intervals of concavity: x^x*[(lnx+1)²+1/x]≥0, therefore f(x) is concave up. inflection points: (0.368,0.692)
Based on these points and information, we can draw the diagram of function f(x)=x^x.