This discussion board is a place to discuss our Daily Challenges and the math and science
related to those challenges. Explanations are more than just a solution — they should
explain the steps and thinking strategies that you used to obtain the solution. Comments
should further the discussion of math and science.

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Stay on topic — we're all here to learn more about math and science, not to hear about your favorite get-rich-quick scheme or current world events.

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Easy Math Editor

This discussion board is a place to discuss our Daily Challenges and the math and science related to those challenges. Explanations are more than just a solution — they should explain the steps and thinking strategies that you used to obtain the solution. Comments should further the discussion of math and science.

When posting on Brilliant:

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## Comments

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TopNewestFifth row, (L-2)=0

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

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

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Fourth step equates zero to zero

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fourth row.

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or 2

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2L-2 is 0

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No, 2L-2 = 2

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

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Fifth St ep is wrongg

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