Calculate the inverse of f(x) = x^3 = 3x^2 + 3x -1

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To find the inverse of the function f(x) = x^3 - 3x^2 + 3x - 1, users suggest starting by identifying a root x0 that satisfies f(x) = 0. Polynomial long division can then be used to simplify the cubic function into a quadratic, which can be factored. There is a discussion about the use of Pascal's Triangle as a potentially easier method for factoring the polynomial. Participants emphasize the importance of following forum rules regarding providing full solutions. Overall, the conversation revolves around strategies for calculating the inverse of the given cubic function.
mooneh
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f inverse for f(x)= x^3-3x^2+3x-1

i thought of taking x common factor x(x^2-3x+3)-1
but i got stuck with the quadratic equation !
HELP...
 
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The coefficients of x^3, x^2, x, and 1 are +1, -3, +3, -1, an interesting pattern. Can you guess a value of x that makes f(x)=0 ? Call that value x0. Then, you can divide f(x) by x-x0 using polynomial long division: http://www.purplemath.com/modules/polydiv2.htm. That will give you a quadratic that you can factorize.
 
better yet to factorise...from x^3-3x^2 is there any factor you can't take out to make it 3x-1?
 
Sorry!, please note that the rules for the Homework Help forums explicitly state that full answers should never be given to students.
 
ooooh my bad. sorry about that cristo... i never saw a post about rules :o

but yeah... mooneh have you ever used or heard of Pascals Triangle before it's much easier to factor than long/synthetic division etc. etc. especially for the particular function you stated... from there you just solve to get the inverse
 
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