do anybody have reasons for this??

L = 2

L(L-1) = 2(L-1)

L2-L = 2L-2

L2-2L = L-2

L(L-2) = L-2

L = 1

Find the mistake in the above maths equations

#Difficult

Easy Math Editor

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Comments

Fifth row, (L-2)=0

Suradnyana Wisnawa - 7 years, 1 month ago

I think the mistake is in the fifth row, where both side divided by (L-2) which is zero

Suradnyana Wisnawa - 7 years, 1 month ago

According to me 5th step is absolutely right but when you do the 2nd step you must mention l is not equal to 1

Ashwin Upadhyay - 6 years ago

Fourth step equates zero to zero

Nikesh Neelakantan - 7 years, 1 month ago

fourth row.

Sajid Askari - 7 years, 1 month ago

or 2

Hany Shenouda - 7 years, 1 month ago

2L-2 is 0

Amey Sadegaonkar - 7 years, 1 month ago

No, 2L-2 = 2

Suradnyana Wisnawa - 7 years, 1 month ago

Simple because of multiplying it by (L-1) it become quadratic ..So it has two solutions 1 & 2.

Aman Chaudhary - 7 years, 1 month ago

Fifth St ep is wrongg

prasanna krishna - 6 years, 8 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}`	$\boxed{123}$