[tex]f (x) = x {}^{2} - x + 1\\ f(2 + h) ={(2 + h)}^{2} - (2 + h) + 1 \\ f(2 + h) = {h}^{2} + 3 \times {h} + 3 [/tex]
[tex]f (x) = x {}^{2} - x + 1 \\ f(2) = {2}^{2} - 2 + 1 \\ f(2) = 4 - 1 \\ f(2) = 3[/tex]
so you do the calculations and you get the result