Question

Expand and simplify (2V5 + 1)(3V5 - 1)

Answer 1

Answer:

$29+\sqrt{5}$

Step-by-step explanation:

Let $\sqrt{5} = a$ for simplicity. now our equation is

(2a+1)(3a-1)

now expand

2a*3a-2a+3a-1 = 6a^2+a-1

remember that $\sqrt{5} = a$

thus we get$6\sqrt{5}^2+\sqrt{5}-1 = 6(5)-1+\sqrt{5}=30-1+\sqrt{5}=29+\sqrt{5}$