Wednesday

November 26, 2014

November 26, 2014

Posted by **lindsay** on Tuesday, July 22, 2014 at 7:25pm.

1. the binomial expansion of (3+2x)^5 simplifying terms. Hence find the binomial expansion of (3+2x)^5 +(3-2x)^5.

- algebra -
**Reiny**, Tuesday, July 22, 2014 at 8:05pm(3+2x)^5

= 3^5 + 5(3^4)(2x) + 10(3^3)(2x)^2 + 10(3^2)(2x)^3 + 5(3)(2x)^4 + (2x)^5

=243 + 810x + 1080x^2 + 720x^3 + 240x^4 + 32x^5

by simple observation that a negative base raised to an odd exponent is negative ....

(3-2x)^5

= 243 - 810x + 1080x^2 - 720x^3 + 240x^4 - 32x^5

(3+2x)^5 +(3-2x)^5

= 243 + 810x + 1080x^2 + 720x^3 + 240x^4 + 32x^5 + 243 - 810x + 1080x^2 - 720x^3 + 240x^4 - 32x^5

= 486 + 2160x^2 + 480x^4

confirmed by Wolfram

http://www.wolframalpha.com/input/?i=expand+%283%2B2x%29%5E5+%2B%283-2x%29%5E5

**Answer this Question**

**Related Questions**

maths - in the binomial expansion of (1+x/k)^n, where k is a constant and n is a...

algebra - Find 1.The first 4 terms of the binomial expansion in ascending powers...

maths - find the first 3 terms in the expansion of (x+4)(1+3x)^-2 as a series in...

same type of binomial theorem question - Question: Find the first 3 terms in the...

binomial expansion - how do you expand the following as a series of ascending ...

Math - Use Pascal's triangle to expand (a+b)^6 and hence find the binomial ...

Binomial expansion - The coefficient of x^2 in the expansion of (4-3x)^n as a ...

Math binomial formula and sequence - a) use the binomial formula to find the 5th...

Algebra2/trig - Hi, I can't figure out what I'm supposed to do on this problem. ...

math binomial expansion - binomial expansion (3a^2-2b^3)^4 is this right? (3a^2...