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5 votes
5 votes
Can some help me with making up a true equation and then I need a false equation.

User Matt Searles
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1 Answer

22 votes
22 votes

A true equiation has a real solution, for example


(3)/(x)+x=(7)/(2)

is true equation because you can find the value of x

multiply X to both sides


\begin{gathered} (3)/(x)(x)+x(x)=(7)/(2)x \\ \end{gathered}
\begin{gathered} 3+x^2=(7)/(2)x \\ x^2-(7)/(2)x+3=0 \end{gathered}

and you can factorize and solve


\begin{gathered} (x-2)(x-(3)/(2))=0 \\ \end{gathered}

It has two solutions for x


\begin{gathered} (x_1-2)=0 \\ x_1=2 \\ (x_2-(3)/(2))=0 \\ x_2=(3)/(2) \end{gathered}

and a false equation has not solution or is not real, for example


\sqrt[]{x}=-2

this cant not be, because when you try to solve x you have:


\begin{gathered} x=(-2)^2 \\ x=4 \end{gathered}

but when you replace to check equality


\begin{gathered} \sqrt[]{(4)}=-2 \\ 2\\e-2 \end{gathered}

User MikeKulls
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