Try using the shortcut for the derivative of a polynomial and then substitute the value of the variable. if f(x) = 2x2+2, then what is the slope of f(x) at x = 7?
[tex]f^{\prime}(x)=(2x^2)^{\prime}+(2)^{\prime}=4x[/tex] Then for the slope just plug x=7 into the differentiated function: [tex]f^{\prime}(x=7)=4.7=28[/tex] Remember that the derivative of a function is the slope of the tangent line at the point of coordinate x.
