Question

(√23 -2)(√23+2) ............

Answer 1

(√23 -2)(√23+2) =23-4=19

Answer 2

$(\sqrt{23}-2)(\sqrt{23}+2);\\\sqrt{23}*\sqrt{23}+\sqrt{23}*2-2*\sqrt{23}-2*2;\\23-4+2(\sqrt{23}-\sqrt{23});\\19+0;\\19$

Answer 3

To simplify the expression (√23 - 2)(√23 + 2), you can use the difference of squares formula, which states that (a - b)(a + b) = a^2 - b^2. In this case, a is √23, and b is 2. So, you can apply the difference of squares formula as follows:

(√23 - 2)(√23 + 2) = (√23)^2 - (2)^2

Now, square both √23 and 2:

(23) - (4)

Now, subtract 4 from 23:

23 - 4 = 19

So, the simplified expression (√23 - 2)(√23 + 2) is equal to 19.