Consider the function f(x)=x2+3x+5\displaystyle {f{{\left({x}\right)}}}={x}^{{2}}+{3}{x}+{5} on the closed interval [4,2]\displaystyle {\left[-{4},-{2}\right]}.

Find the exact value of the slope of the secant line connecting (4,f(4))\displaystyle {\left(-{4},{f{{\left(-{4}\right)}}}\right)} and (2,f(2))\displaystyle {\left(-{2},{f{{\left(-{2}\right)}}}\right)}.

m=\displaystyle {m}=  

By the Mean Value Theorem, there exists c\displaystyle {c} in (4,2)\displaystyle {\left(-{4},-{2}\right)} so that m=f(c)\displaystyle {m}={f}'{\left({c}\right)}. Find all values of such c\displaystyle {c} in (4,2)\displaystyle {\left(-{4},-{2}\right)}. Enter exact values. If there is more than one solution, separate them by a comma.

c=\displaystyle {c}=