Answer :
Step-by-step explanation:
[tex]\frac{f(7+h)-f(7)}{h}\\=\frac{\frac{1}{(7+h)+3}-\frac{1}{7+3}}{h}\\=\frac{\frac{1}{10+h}-\frac{1}{10}}{h}\\=\frac{\frac{10-(10+h)}{10(10+h)}}{h}\\=\frac{-h}{10(10+h)h}}\\=\frac{-1}{10h+100}} \text { for h} \neq 0[/tex]
so a=10, b=100