Order of operations doubt on this expression

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SUMMARY

The discussion centers on the expression $\frac{1}{2}*2x*x-2$ and the differing results obtained from two methods of simplification. The first method simplifies directly to $x^2 - 2$, while the second method incorrectly simplifies to $x^2 - 1$. The key takeaway is that the order of operations dictates performing multiplication before subtraction, confirming the first method as the correct approach. The second method would only be valid if the expression were structured as $\frac{1}{2}(2x\cdot x-2)$.

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Let's say that we have this expression,

$\frac{1}{2}*2x*x-2$

So now solving this in one method we can

$\frac{1}{\cancel 2}*\cancel2x*x-2=x^2-2$

In another way

$\frac{1}{2}*2x*x-2=\frac{2x^2-2}{2}=x^2-1$

What is the reason that I get two different answers ? I hope that both ways are valid

Many THanks :)
 
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The order of operations dictates that we do multiplication/division first before subtraction, so the first method is correct. The second method you used would be valid if we had:

$$\frac{1}{2}(2x\cdot x-2)$$
 

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