SOLUTION: Hello, I need help with the following problems as I get an error message on my calculator! its: 1. sqrt x-1=3 ( I don't know the square root symbol!) 2. sqrt x^3=8 3. 3

Question 82458: Hello,
I need help with the following problems as I get an error message on my calculator!
its:
1. sqrt x-1=3 ( I don't know the square root symbol!)
2. sqrt x^3=8
3. 3 sqrt x^2=4
4. Is sqrt x^2 power an identity (true for all values of x)?
Thanks so much for your help!! :)

Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
1. sqrt(x-1) = 3
:
(Sqrt(x-1))^2 = 3^2; square both sides
x - 1 = 9; gets rid of the radical
x = 9 + 1
x = 10
Check: sqrt(10-1) = 3
:
2. sqrt(x^3) = 8
Square both sides again:
x^3 = 64
x = CubeRt(64)
x = 4
Check: Sqrt(4^3) = 8
:
3. 3*sqrt(x^2) = 4
Square both sides:
(3*sqrt(x^2) = 4^2
9*(x^2) = 16
x^2 = 16/9
x = Sqrt(16/9)
x = +/-4/3
Check 3 * sqrt[(4/3)^2] = 4 (on a calc)
:
4. Is sqrt x^2 power an identity (true for all values of x)?
I think it is
RELATED QUESTIONS
I keep trying this on my calculator and i keep getting an error message. Can anyone help... (answered by Edwin McCravy)

HI I NEED HELP WITH A QUESTION I DON;T KNOW TO REACH THE CONCLSUION I KNOW NOTHING ABOUT... (answered by Alan3354)

I need help with 2 problems using my new TI-84 Plus: 1.find x: log x=3.8893 The... (answered by edjones,josmiceli)

These problems I have been working on all weekend, and I do not understand. My grade and... (answered by stanbon)

Quick question about dividing with decimals. I need to complete long division on... (answered by ankor@dixie-net.com,math_helper,josgarithmetic)

i need help on absolute values please. this is what i have tried so far on my problems:... (answered by mananth,josgarithmetic)

Hello! I am very confused on a question for homework, and don't know where to start. It... (answered by ikleyn)

Hello, i need help on solving this equation. I dont even know where to start. t-2/t-1= (answered by ankor@dixie-net.com)

Hello, Need help finishing my assignment. i am stuck on a domain question? Find the... (answered by jim_thompson5910)