Solve for real solution of the system below:
\displaystyle \left\lfloor{x^3}\right\rfloor+\left\lfloor{x^2}\right\rfloor+\left\lfloor{x}\right\rfloor=\left\{x\right\}-1.
My solution:
First, observe that the LHS of the equality must yield an integer, this tells us the fractional part of x must be a zero, so this turns the whole equation as:
\displaystyle x^3+x^2+x=-1\\x^3+x^2+x+1=0\\(x+1)(x^2+1)=0
This implies x=-1 is the only real solution to the system.
Good solution on greatest integer function
ReplyDeleteThanks so much for your sweet compliment, Elton! :D
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