# transpose issue

• May 11th 2011, 03:43 AM
anthonye
transpose issue
Hi;
I have make u the subject of v^2 = u^2 + 2as.

The solution is u = sqrt(v^2 - 2as).

the last opporation is take sqrt of both sides so I need parenthesis because the
last opporation is sqrt.

but in another example I have a solution of sqrt 2(s-v)/a.
why dont I need parenthesis around the fraction.

Thanks.
• May 11th 2011, 03:53 AM
HappyJoe
If in the last solution, you meant to have all of the expression 2(s-v)/a under the square root, then parantheses should have been included for the sake of readability: It should have been sqrt(2(s-v)/a).

If parantheses are not included, then it becomes unclear exactly what part of the expression belongs under the square root. For instance, I could also read "sqrt 2(s-v)/a" as

sqrt(2)*(s-v)/a,

or

sqrt(2(s-v))/a,

these being entirely different expressions.
• May 11th 2011, 04:02 AM
anthonye
Thanks for your quick reply Happyjoe the equation is t^2 = 2(s - v ) / a.

seem as I need to take the entire sqrt of both sides the solution should be t = sqrt(2(s - v) / a) is the correct.
Because I'm taking the sqrt root of everthing on the rhs parenthesis should be used.
• May 11th 2011, 11:12 AM
HappyJoe
Yes, I agree with what you're saying. :)
• May 12th 2011, 08:26 AM
anthonye
But why do I see it in lots of places without parenthesis.

Thanks
• May 12th 2011, 10:55 AM
HappyJoe
Because of sloppyness, I assume.

There could also be some standing assumption that if parantheses are left out, then it is implicit that everything after the square root belongs under the root. This would be a rather annoying convention, so I do suspect sloppyness.