Consider this equation.(adsbygoogle = window.adsbygoogle || []).push({});

[tex]x^3 = x + 6[/tex]

If we solve for x we'll get x=2

Now if we differentiate both sides with respect to x, we get

[tex]3x^2 = 1[/tex]

If we now put x=2, we get

[tex]3(2)^2 = 12 = 1[/tex]

Which is of course wrong. So how can we differentiate both sides of an equation when the value of x changes after the differentiation?

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# How are we able to differentiate both sides of an equation?

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