- #1
Davewilliams
- 4
- 0
I was on the bus home from a hockey match and my maths teacher asked what is the the square root of 9.
he said it was ±3 but i thought it was only +3
he put forth
-3 x-3 = 9 and 3x3 =9 so it was both so 9^1/2 = ±3
i said that 3^2=9 then 3=9^1/2 so 3=3 and not 3=-3 so 3 ≠±3
doing it algebraically
a^2=b
a=b^1/2 but instead i would write a=±(b^1/2)
so if the square root is already plus and minus whey have the second plus and minus?
he said it was ±3 but i thought it was only +3
he put forth
-3 x-3 = 9 and 3x3 =9 so it was both so 9^1/2 = ±3
i said that 3^2=9 then 3=9^1/2 so 3=3 and not 3=-3 so 3 ≠±3
doing it algebraically
a^2=b
a=b^1/2 but instead i would write a=±(b^1/2)
so if the square root is already plus and minus whey have the second plus and minus?