How do you simplify [(x+4)^3/4(x+2)^-2/3 - (x+2)^1/3(x+4)^-1/4]/ [(x+4)^3/4]^2(x+4)34(x+2)23(x+2)13(x+4)14[(x+4)34]2?

1 Answer
Apr 4, 2015

4/(3(x+4)^3) *[1/(x+2)^2 - (x+2)/(x+4)^4]43(x+4)3[1(x+2)2x+2(x+4)4]

Given:
(((x+4)^3)/4 * (x+2)^-2/3 - (x+2)/3 * (x+4)^-1/4)/((x+4)^3/4)^2(x+4)34(x+2)23x+23(x+4)14((x+4)34)2

Let a = x+4a=x+4 and b=x+2b=x+2
((a^3)/4 * b^-2/3 - b/3 * a^-1/4)/(a^3/4)^2a34b23b3a14(a34)2

When you divide by a fraction, you are multiplying the reciprocal:
[(a^3)/4 * b^-2/3 - b/3 * a^-1/4] * (4/a^3)^2[a34b23b3a14](4a3)2

Change negative exponents to reciprocals with positive exponents:
[(a^3)/4 * 1/(3b^2) - b/3 * 1/(4a)] * (4/a^3)^2[a3413b2b314a](4a3)2

[a^3/(12b^2) - b/(12a)] (16/a^6)[a312b2b12a](16a6)

(16a^3)/(12a^6b^2) - (16b)/(12a^7)16a312a6b216b12a7

4/(3a^3b^2) - (4b)/(3a^7)43a3b24b3a7

Factor out 4/(3a^3)43a3:

4/(3a^3) [1/b^2 - b/a^4]43a3[1b2ba4]

Substitute back in x+4x+4 and x+2x+2
4/(3(x+4)^3) * [1/(x+2)^2 - (x+2)/(x+4)^4]43(x+4)3[1(x+2)2x+2(x+4)4]

Hope that was helpful.