Find the values of the following expressions when x=-1:
(i) 2x - 7
(ii) -x + 2
(iii) x2 + 2x +1
(iv) 2x2- x -2
(i) 2x - 7
Put x = -1
= 2(-1) - 7
= -2 - 7
= -9
(ii) -x + 2
Put x = -1
= -(-1) + 2
= 1 + 2
= 3
(iii) x2 + 2x + 1
Put x = -1
=(-1)2 + 2(-1) + 1
=1 - 2 + 1
=0
(iv)2x2 - x - 2
Put x = -1
=2(-1)2 - 1 -2
= 2(1) - 3
=2 - 3
= -1