SOLUTION: Given that f(x) = 5-7x-2x^2 for x is an element of R. Write down the range of the function f(x).

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Question 1184852: Given that f(x) = 5-7x-2x^2 for x is an element of R.
Write down the range of the function f(x).
Answer by josgarithmetic(39625) About Me  (Show Source):
You can put this solution on YOUR website!
Maximum point at f%28-7%2F4%29=59%2F2 so the range is the values y which less than or equal to 59/2 or 29.5

f%28x%29=-2x%5E2-7x%2B5
-2%28x%5E2%2B%287%2F2%29x%29%2B5
You need to use %287%2F4%29%5E2 for completing-the-square.
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f%28x%29=-2%28x%2B7%2F4%29%5E2%2B59%2F2--------showing the vertex is maximum point for f, and range is y%3C=59%2F2.