Confused =[ (1 Viewer)

[Apex]

2/(sqrt2+1)/2

How do i make this into a single fraction?

i tried 2/(sqrt2+1) x 1/2

but that was incorrect. Help plz! Kind of a simple question 15 days out from the exam or so, but i'm stuck.

 

[mirakon]

Multiply the numerator 2 by 2= 4

Multiply denominator (sqrt2+1)/2 by 2= (sqrt2+1)

Thereofre the answer is 4/(sqrt2+1)

Oh, and rationalise the denomiator.

Hope I helped.

 

[Apex]

Multiply the numerator 2 by 2= 4

Multiply denominator (sqrt2+1)/2 by 2= (sqrt2+1)

Thereofre the answer is 4/(sqrt2+1)

Oh, and rationalise the denomiator.

Hope I helped.

Awesome thanks, seems so simple now that you explained it to me.

EDIT: i thin kthat is the wrong answer, my book says 1/(srt2+1) ?

 

[Apex]

bump

 

[Drongoski]

Awesome thanks, seems so simple now that you explained it to me.

EDIT: i thin kthat is the wrong answer, my book says 1/(srt2+1) ?

Your question is ambiguous.

if: 2/{(sqrt(2) + 1)/2 } then mirakon's answer is right.

if: {2/(sqrt(2) + 1)}/2 then it is what you say.

 

[paddy86]

Typing the expression the way you do would indicate you have a hazy grasp of such expressions.

lol

 

[letsdie45]

(2/sqrt(2) +1)/2 = [2/sqrt(2) + 1] * 1/2 = 1/sqrt(2)+1

 

[Drongoski]

lol

Oh dear. I thought I might be misunderstood and cause needless offence; so I quickly deleted my comments but not quickly enough.

Let me explain. When my students have difficulty I try to figure out the nature and/or the source of such a difficulty. The expression posed is like: 24/3/4

It is ambiguous.

Is it?: (24/3)/4 = 8/4 = 2

or

Is it?: 24/(3/4) = (24 x 4) / 3 = 32

Some Yr 7 Yr 8 Maths texts claim the way to treat such expressions is, scanning from left to right, carry out the operations in the order of the operators ("/" in this case). Using this rule we get the answer 2 because we do 24/3 1st, giving 8 and then divide this by 4. In my view this is nonsense. There are no such rules. You avoid such ambiguity by the proper use of parentheses or brackets or braces.