Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °
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Hey guys, apparently it's incorrect to put the absolute value signs, can anybody confirm this? Or support it? I know it works out mathematically but I was told it's still wrong.
yeah it all makes sense, thanks guys
All of the above is correct. They've hidden it with lots of unnecessary complications, but what they're basically doing is saying that as x² = (-x)², then x = -x, even though it doesn't.
step 5. there you should have absolute value.
when you take the square root, you need the ± which gives you a few different combinations...this "proof" just uses one combination that does not work.
1) 16 - 36 = 25 - 45