If f(x) = 3x +x^2, what is f(-2)?
f(-2) = 3(-2) + (-2)2 = -6 + 4 = 2First you need to substitute -2 for each value of x in the function. Then you need to simplify the expression by multiplying -2 by 3 and by squaring -2. (Hint: negative numbers squared are always positive). Finally just add the two numbers.
WB
Related Maths GCSE answers
All answers ▸What is differentiation and what does it actually mean?
Two shops have deals for purchasing pens: "3 for £2" and "5 for £3" . Mr. Papadopoulos wants to buy 30 pens for his class in school, which deal should he use if he wants to spend the least amount of money possible, and how much will he spend?
Work out 2 7/15 -1 2/3
Factorise 4xy-6xz