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Question
Getting the zero of a function.
4X^3-24X^2-X+6
Hello Ashley,
So, you want to solve 4X^3-24X^2-X+6=0...
Factor by grouping: 4x^2(x-6)-1(x-6)=0
Now factor out the (x-6) to get: (x-6)(4x^2-1)=0
Now factor the 4x^2-1 to get: (x-6)(2x+1)(2x-1)=0
Now set each factor to zero and solve: x-6=0 OR 2x+1=0 OR 2x-1=0
==> x=6 OR x=-1/2 OR x=1/2
OK?
Abe
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Answers by Expert:
Abe Mantell
Expertise
Hello, I am a college professor of mathematics and regularly teach all levels from elementary mathematics through differential equations, and would be happy to assist anyone with such questions!
Experience
Over 15 years teaching at the college level.
Organizations
NCTM, NYSMATYC, AMATYC, MAA, NYSUT, AFT.
Education/Credentials
B.S. in Mathematics from Rensselaer Polytechnic Institute
M.S. (and A.B.D.) in Applied Mathematics from SUNY @ Stony Brook
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