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    I had an exam today and I was stuck appon expanding this bracket I don't even know what's called in math can someone help with this problem.

    The question was finding the derivative of this function by limit method

    F(x)= (x-1)^3

    I stucked here when adding the (h)
    Lim(h ~0) [(x+h-1)^3 -(x-1)]/h
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    answers x ^2 + 8
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    Can you explain it if possible if not thanks for your help but I think that's not the right answer
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    (Original post by Zayn110)
    I had an exam today and I was stuck appon expanding this bracket I don't even know what's called in math can someone help with this problem.

    The question was finding the derivative of this function by limit method

    F(x)= (x-1)^3

    I stucked here when adding the (h)
    Lim(h ~0) [(x+h-1)^3 -(x-1)]/h
    You'd want to rewrite (x-1+h)^3 - (x-1)^3 = (x-1)^3+3h(x-1)^2 + 3h^2 (x-1) + h^3 - (x-1)^3 then proceed from there.
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    (Original post by Jackmo1112)
    answers x ^2 + 8
    No it's not.
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    (Original post by RDKGames)
    No it's not.
    Cheers Sherlock
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    (Original post by RDKGames)
    You'd want to rewrite (x-1+h)^3 - (x-1)^3 = (x-1)^3+3h(x-1)^2 + 3h^2 (x-1) + h^3 - (x-1)^3 then proceed from there.
    Thank a lot man I really appreciate it, btw what's this type of expanding is called? Does it have a specific name I'm not really experienced with mathematical terms.
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    (Original post by Zayn110)
    Thank a lot man I really appreciate it, btw what's this type of expanding is called? Does it have a specific name I'm not really experienced with mathematical terms.
    Binomial expansion.
 
 
 
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