HELP!! i need help with these(Headbang)

Q1 Show that:

Ö2+1

----- = 3 +2Ö2

Ö2-1

Q2

Ö5-1

----- = 3+Ö5

Ö5-2

Q3 express : in the form kÖ5

1 1

---- - ----

3Ö5 2Ö20

Printable View

- October 13th 2008, 09:05 AMkelliSurds please help
HELP!! i need help with these(Headbang)

Q1 Show that:

Ö2+1

----- = 3 +2Ö2

Ö2-1

Q2

Ö5-1

----- = 3+Ö5

Ö5-2

Q3 express : in the form kÖ5

1 1

---- - ----

3Ö5 2Ö20 - October 13th 2008, 09:15 AMbatman
Multiply the first by (sqrt(2)+1)/(sqrt(2)+1) to get

(sqrt(2)+1)^2/((sqrt(2)-1)(sqrt(2)+1)) = (sqrt(2)+1)^2/(sqrt(2)^2-sqrt(2)+sqrt(2)-1) = (2+2sqrt(2)+1)/1 = 3+2sqrt(2)

The second and third go in exactly the same way.