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mathater
Need help with the final step:: Let the function f(x) be defined by the equation y = f(x), where x and f(x) are real numbers. f(x) = 4 − x^2 f(9) = -77 f(-7) = -45 f(k) = 4-k^2 f(k2 − 8) = ??
Basically you just plug in the entire input expression in place of the x so f(k2 - 8) = 4 - (k2 - 8)^2
suppose to have read as f(k^2-8)=
Still valid if you read the answer the same way. =) f(k^2 - 8) = 4 - (k^2 - 8)^2