Find the value of each of the following expressions for the values of the letters given against each.

i)x^2 + 3x + 5; x = 3

ii)a^2 + 2ab − 7; a = −1, b = 2.

iii)(2x+3y-9z^2)/(7+2y-z^3); x = 2, y = −1, z = −2.

iv)1/(x − 3); x = 3