Inkling

Breakthrough

01:02Resolved

About “Multiplying the inner derivative”

Why it was flagged

Paused 8s while 24 words were spoken
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Erased this and rewrote it 2s later

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After · rewritten

What you changed: dy/dx = 2(3x + 1) to dy/dx = 2(3x + 1) times 3 = 6(3x + 1)

Likely mix-up: Stopped after the outer derivative and forgot to multiply by the inner derivative, 3.

What the lecture was saying

00:52–01:12

“…three x plus one. The outer derivative is two u, so two times three x plus one. Then we multiply by the derivative of the inside, which is three. So the answer is six times three x plus one. A common mistake is to stop after the outer derivative and forget to multiply by three. Another way to write it uses…”

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