If a = √3 - √2, b = √3 + √2, then

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If a = √3 - √2 , b = √3 + √2 , then the value of
√3 + √2 √3 - √2

a² + b² is :
b a

1. 900
2. 970
3. 1030
4. 930

Correct Option: B

As we know from given question,

a =	√3 - √2
	√3 + √2

Multiply and divide by √3 - √2, We will get

a =	√3 - √2	x	√3 - √2
	√3 + √2		√3 - √2

a =	( √3 - √2)²
	3 - 2

a = 3 + 2 - 2√6
a = 5 - 2√6
Again We know from the given question,

b =	√3 + √2	= 5 + 2√6
	√3 - √2

We will get the value by adding a and b,
⇒ a + b = 5 - 2√6 + 5 + 2√6
⇒ a + b = 10;
We will get the value by multiplying a and b,
a x b = ( 5 - 2√6 ) x ( 5 + 2√6 ) = 5 x 5 - 4 x 6 = 25 - 24 = 1
Now we will calculate the value of

	a²	+	b²
	b		a

=	a³ + b³
	ab

=	( a + b )³ - 3ab( a + b )
	ab

= 10³ - 3 x 10 = 1000 - 30 = 970

If a =	√3 - √2	, b =	√3 + √2	, then the value of
	√3 + √2		√3 - √2