Question

The value of (3+√5 ) (3-√5 ) is...

Answer 1

Answer:

4

Step-by-step explanation:

(a+b)(a-b)=a^2-b^2

here a=3, b=√5

(3+√5)(3-√5)= 9-5=4

Answer 2

Answer:

(3 + √5) (3 - √5) = 4

Step-by-step explanation:

Given:

Expression - (3 + √5) (3 - √5)

To Find:-

The value of (3+√5 ) (3-√5 ) =?

Formula/Identity Used:-

(a + b) ( a - b) = a² - b²

Procedure:-

Putting the known values in:-

$\implies \sf (3+\sqrt{5} )(3-\sqrt{5} )$

$\implies \sf (3+\sqrt{5} )(3-\sqrt{5} ) = 3^2 - 5$

$\implies \sf (3+\sqrt{5} )(3-\sqrt{5} ) = 9 - 5$

$\implies \sf (3+\sqrt{5} )(3-\sqrt{5} ) = 4$

Answer = 4

Points to Remember:-

• - Natural Numbers: 1,2,3,4,5,6...

• - Whole Numbers: 0,1,2,3,4,5,6...

• - Integers: .....-5,-4,-3,-2,-1,0,1,2,3,4,5..

• - Rational Numbers: 1/2, 1/3, 1/4...

• - Irrational Numbers: 2^1/2, 22/7, etc

• - Real numbers: All rational + Irrational numbers