Question

multiply, simplify where possible. (sqrt8 - sqrt3)(sqrt8 +sqrt3)

Answer 1

If you let x = sqrt(8) and y = sqrt(3), you get

(x-y)(x+y)

which becomes

x^2-y^2

Answer 2

Some trick here xD

\(\Large \color{Black}{\Rightarrow (a - b)(a + b) = a^2 - b^2 }\)

Answer 3

\[(\sqrt{8}-\sqrt{3})(\sqrt{8}+\sqrt{3})\]

Answer 4

Then you can replace 'x' with sqrt(8) and y with sqrt(3) to get

(sqrt(8))^2 - (sqrt(3))^2

Answer 5

what's next?

Answer 6

(64-9)(64+9) ??

Answer 7

not quite, I see what you're saying though

Answer 8

(sqrt(8))^2 = 8 since the square and square root undo each other

so (sqrt(3))^2 = 3


This means

(sqrt(8))^2 - (sqrt(3))^2

becomes

8 - 3 = 5


So (sqrt(8) - sqrt(3))(sqrt(8) +sqrt(3)) = 5