SOLUTION: I am in need of some help with these question Simplify by combining like terms: x Sqaure root 18- 3 square root 8x^2 and simplify each radical expression (square root 3

Algebra ->  Radicals -> SOLUTION: I am in need of some help with these question Simplify by combining like terms: x Sqaure root 18- 3 square root 8x^2 and simplify each radical expression (square root 3      Log On


   

Question 90864: I am in need of some help with these question
Simplify by combining like terms:
x Sqaure root 18- 3 square root 8x^2
and
simplify each radical expression
(square root 3+5)(square root 3-3)

Thank you for your help
Answer by malakumar_kos@yahoo.com(315) About Me  (Show Source):
You can put this solution on YOUR website!

Simplify by combining like terms:
x Sqaure root 18- 3 square root 8x^2
and
simplify each radical expression
(square root 3+5)(square root 3-3)
1) x.(sq rt 18)-3.(sq rt 8x^2) (sq r 18 = sq rt 9*2 = 3.sq rt 2)

(sq rt 8x^2 = sq rt x^2 sq rt 4*2
= x.2 sq rt 2)
= x.3.sq rt 2- 3.x.2. sq rt 2

= sq rt 2(3x - 6x)
= -3x sq rt 2

2) (sq rt 3+5). (sq rt 3 - 3) ( use (x+a).(x-b) = x^2+x(a-b)+ab)

= (sq rt 3)^2+ sq rt 3 (5-3) + 5(-3)
= 3 + 2.sq rt 3 -15