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Expert: Sherry Wallin - 10/31/2009


Question
how to calculate this?

(x-1.2)(x-1.3)(x-1.5)

Answer
fzlan87~
You calculate this exactly the same way you would calculate (x-1)(x-2)(x-3). Use foil or the distributive law to multiply the first two factors and then take that answer and multiply it by the 3rd factor. In my example (x-1)(x-2)= x^2 -2x -1x +(-1)(-2) = x^2 -3x + 2
Now multiply this by the 3rd factor:
(x-3)(x^2 -3x + 2) = x(x^2 -3x + 2)-3(x^2 -3x + 2)=x^3-3x^2+2x-3x^2-3(-3x)-3(2) = x^3 -6x^2 +11x -6

Yours would be set up this way:
(x-1.2)(x-1.3)=x*x -1.3x-1.2x+(-1.2)(-1.3)simplify this, then multiply the simplified answer by(x-1.5)

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Sherry Wallin

Expertise

I can answer most questions up through Calculus and some in Number Theory and Abstract Algebra.

Experience

I have had my Bachelor's Degree since 1987 and have been a teacher since 1988. I earned my Masters Degree in Mathematics May 2010. I have been teaching at the same community college since 2002.

Education/Credentials
I have taught 12 years at the community college level, medical college, and technical college as well as a high school instructor and alternative education instructor and charter school instructor.

Awards and Honors
Master's GPA 3.56 Bachelor's GPA 3.34 Post grad work not degree related GPA 4.0

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