Math Tricks of equating 1=0

Whats possibly wrong in this equation.. have seen these stuffs when I was small but why isn't it correct ?

9 = (-3)^2

9 = (3)^2

accordingly, (-3)^2 = (3)^2 => -3 = 3 => 6 = 0 and hence infinite solutions arise after this showing n=0 for all n belonging to real numbers. :P

#Logic #Opinions

Easy Math Editor

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Comments

the fallacy here is that the rule of taking the root of an equation only holds true when both numbers are positive, which -3 is not. Therefore, algebra continues to hold true.

This is a useful website for these types of problems http://en.wikipedia.org/wiki/Mathematical_fallacy

Gaurav Sharma - 8 years, 1 month ago

Lol. Wikipedia is a "useful" site. only americans

Justin Wong - 8 years, 1 month ago

We know that while taking roots we have to take modulus on both the sides i.e. (in this problem) after (-3)^ 2 =(3)^ 2
|-3| =|3|

which gives us 3=3 which is always true

ANSHUL AGARWAL - 8 years, 1 month ago

When taking square root...be careful to take modulus on both sides...which gives u 3=3!!

Tanya Gupta - 7 years, 3 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$