How do you simplify (9a^3b^4)^(1/2)(9a3b4)12?

2 Answers
Aug 30, 2016

3b^2a^(3/2)3b2a32 or 3ab^2sqrta3ab2a depending on what is meant by "simplify".

Explanation:

Exponents distribute across multiplication, so

(9a^3b^4)^(1/2) = 9^(1/2)(a^3)^(1/2)(b^4)^(1/2)(9a3b4)12=912(a3)12(b4)12

Now use 9^(1/2) = sqrt9 = 3912=9=3.

Also use (x^a)^b = x^(ab)(xa)b=xab, to get

(a^3)^(1/2) = a^(3/2)(a3)12=a32 which can be written a*a^(1/2) = a sqrtaaa12=aa

and (b^4)^(1/2) = b^2(b4)12=b2.

(9a^3b^4)^(1/2) = 9^(1/2)(a^3)^(1/2)(b^4)^(1/2)(9a3b4)12=912(a3)12(b4)12

= 3a^(3/2)b^2=3a32b2 " " (which is simpler in some sense)

= 3asqrtab^2=3aab2

which is not as easy to read as putting the radical last

= 3ab^2sqrta=3ab2a.

Aug 30, 2016

3a^(3/2)b^23a32b2

Explanation:

Using the color(blue)"laws of exponents"laws of exponents

color(orange)"Reminder " color(red)(|bar(ul(color(white)(a/a)color(black)((a^m)^n=a^(mn))color(white)(a/a)|)))

This law applies to each value inside the bracket.

rArr9^(1xx1/2xxa^(3xx1/2)xxb^(4xx1/2)=9^(1/2)a^(3/2)b^2

color(orange)"Reminder " color(red)(|bar(ul(color(white)(a/a)color(black)(a^(1/2)=sqrta)color(white)(a/a)|)))

rArr9^(1/2)=sqrt9=3

rArr(9a^3b^4)^(1/2)=3a^(3/2)b^2