Question

5.SIMPLIFY : (2√3 - 2√5 ) (2√3 + 2√5 )

Answer 1

Answer:

How do I simplify (2+√5/2-√5) + (2-√5/2+√5)?

The only clear way to solve it successfully is by making the two fractions’ denominators one. And the easy way to do that in your case to multiply the first by 2+√5 and the second by 2-√5. So, you obtain:

(2+√5/2-√5) + (2-√5/2+√5)= ((2+√5)*(2+√5)/(2-√5)*(2+√5)) + ((2-√5)*(2-√5)/(2+√5)*(2-√5))= ((2+√5)²+(2-√5)²)/((2+√5)*(2-√5))=((4+5+4√5)+(4+5–4√5))/(2²-√5²)=(9+9+4√5–4√5)/(4–5)=18/(-1)=-18

The mathematical properties used:

(a+b)²=a²+2ab+b² , (a-b)²=a²-2ab+b² and (a+b)*(a-b)=a²-b²

I hope this helped. Good Luck!

Answer 2

Step-by-step explanation:

isme 3rd identity lagegi

a²-b²

wali

lagake dekhte hai

(2√3)²- (2√5)²

= 4*3- 4*5

= 12-20

= -8

happy