f(x)=xkx−x2 ⇒f′(x)=2kx−x23kx−4x2
As per the given condition f′(x)≥0 for x∈[0,3]
⇒3kx−4x2≥0 for x∈[0,3]
⇒3k−4x≥0 for x∈[0,3]
⇒k≥34x for x∈[0,3]
⇒k≥4 . So minimum value of k is m=4.
Now f(x)=x4x−x2
Since given function in increasing hence maximum value will occur at x=3
⇒f(3)=34×3−32=33,M=33
Hence (m,M)=(4,33)