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The function f(x)=x^9+3x^7+64 is increas...

The function `f(x)=x^9+3x^7+64` is increasing on (a) `R` (b) `(-oo,\ 0)` (c) `(0,\ oo)` (d) `R_0`

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`f(x)=x^9+3x^7+64`
` f^′(x)=9x^8+21x^6`
` =3x^6(3x^2+7)`
function is increasing
`3x^6(3x^2+7) gt 0`
`Rightarrow ` function is increasing on R
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