\"\"

The function \"f\\left.

Find \"\"\"f\\left.

Substitute \"x=a\" in \"f\\left.

\"f\\left.

\"\"

Find \"f\\left.

Substitute \"x=a+h\" in \"f\\left.

\"f\\left

\"f\\left.

\"\"

Find  \"\\frac{f\\left.

Substitute the values of \"f\\left and \"f\\left.

\"\\frac{f\\left

                                  \"=\\frac{7a+7h-3-7a+3}{h}\"

\"\\frac{f(a+h)-f(a)}{h}=7\".

\"\"

\"f\\left.

\"f\\left.

\"\\frac{f(a+h)-f(a)}{h}=7\".