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
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