Advertisements
Advertisements
प्रश्न
Simplify the following expressions:
`(5 + sqrt7)(5 - sqrt7)`
Advertisements
उत्तर
We know that `(a + b)(a - b) = a^2 - b^2`We will use this property to simplify the expression
`(5 + sqrt7)(5 - sqrt7)`
`:. (5 + sqrt7)(5 - sqrt7) = 5^2 - (sqrt7)^2`
`= 5 xx 5 - sqrt7 xx sqrt7`
`25 - sqrt(7 xx 7)`
`= 25 - (7^2)^(1/2)`
`= 25 - 7^1`
= 18
Hence the value of expression is 18.
APPEARS IN
संबंधित प्रश्न
Simplify the following expressions:
`(sqrt5 - sqrt3)^2`
Rationalise the denominator of the following
`(3sqrt2)/sqrt5`
Find the value to three places of decimals of the following. It is given that
`sqrt2 = 1.414`, `sqrt3 = 1.732`, `sqrt5 = 2.236` and `sqrt10 = 3.162`
`(sqrt5 + 1)/sqrt2`
In the following determine rational numbers a and b:
`(sqrt3 - 1)/(sqrt3 + 1) = a - bsqrt3`
Write the rationalisation factor of \[7 - 3\sqrt{5}\].
Simplify \[\sqrt{3 - 2\sqrt{2}}\].
Simplify the following expression:
`(sqrt5-sqrt2)(sqrt5+sqrt2)`
The value of `(sqrt(32) + sqrt(48))/(sqrt(8) + sqrt(12))` is equal to ______.
Rationalise the denominator of the following:
`sqrt(6)/(sqrt(2) + sqrt(3))`
Rationalise the denominator of the following:
`(3sqrt(5) + sqrt(3))/(sqrt(5) - sqrt(3))`
