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2 years ago

Find the zeros of the function. f(x)=-3x^2+75

2 answers:

6 0

Add 3x^2 to both sides. 3x^2=75. Divide by 3 on both sides to get x^2=25. Then square root each side to get x=5 or -5. Hope this helps! ;)

iVinArrow [24]2 years ago

4 0

0=-3x^2+75
3x^2=75
x^2=25
x=+-5

Final answer: x=-5, x=5

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$\displaystyle \sum_{n=1}^\infty \left|\frac{(-1)^n (n^2+9)}{e^n}\right|=\sum_{n=1}^\infty \frac{n^2+9}{e^n} < \sum_{n=1}^\infty \frac{n^2}{e^n} < \sum_{n=1}^\infty \frac1{e^n}=\frac1{e-1}$

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