Question

if the function f(x)=x2-kx+5is increasing on [2,4] thenwhat is value of k

Answer 1

F(2)=4-2k+5=9-2k
F(4)=16-4k+5=21-4k
Since F(x) is increasing F(4)>F(2)
21-4k>9-2k
12>2k
6>k
K<6