Find the value of x (either odd or even)..

5x^7 + 3x^4 = 241

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- Mar 17th 2017, 04:23 AM #1

- Mar 17th 2017, 05:44 AM #2

- Mar 17th 2017, 07:53 AM #3
## Re: what is the value of x?

your equation does not have an integer solution.

let $f(x)=5x^7+3x^4-241$

note $f(1)=-233$ and $f(2)=447$ ... since the function is continuous, there exists a value of $x$ in the interval $(1,2)$ where $f(x) = 0$

attached is a graph showing that single real zero

- Mar 17th 2017, 09:20 AM #4

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## Re: what is the value of x?

Go here and enter your equation:

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- Mar 17th 2017, 10:58 AM #5

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## Re: what is the value of x?

The reason I know your equation has no solutions in integers is A) if x is an odd integer,

then the left-hand side is even because is it the sum of two odd numbers, and B) if x

is an even integer, then the left-hand side is even because is it the sum of two even

numbers.

No specific values of x need to be substituted to do the problem. The corresponding

graph of f(x) = 5x^7 + 3x^4 need not be checked.