Question

Can someone clearly explain and workout Q19? Much appreciated

Answer 1

The x coefficient is 2
Take half of 2 to get 2/2 = 1
Square 1 to get 1^2 = 1

Add and subtract 1 to the expression. This is the same as adding 0. 

x^2 + 2x + 2
x^2 + 2x + 2 + 0
x^2 + 2x + 2 + (1-1)
(x^2 + 2x + 1) + 2 - 1
(x+1)^2 + 1

Answer: (x+1)^2 + 1