Advertisements
Advertisements
प्रश्न
If m – n = 16 and m2 + n2 = 400, then find mn.
योग
Advertisements
उत्तर
Given, m – n = 16 and m2 + n2 = 400.
Since, (m – n)2 = m2 + n2 = 2mn ...[Using the identity, (a – b)2 = a2 + b2 – 2ab]
∴ (16)2 = 400 – 2mn
⇒ 2mn = 400 – (16)2
⇒ 2mn = 400 – 256
⇒ 2mn = 144
⇒ `mn = 144/2`
⇒ mn = 72
shaalaa.com
क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
APPEARS IN
संबंधित प्रश्न
Expand `("a"-1/"a")^2`
(p – q)2 = _______________
The factors of x2 – 6x + 9 are
Using identity, find the value of (4.9)2
Simplify: (a + b)2 – (a – b)2
(a – b) ______ = a2 – 2ab + b2
Factorise the following, using the identity a2 – 2ab + b2 = (a – b)2.
a2y2 – 2aby + b2
Factorise the following, using the identity a2 – 2ab + b2 = (a – b)2.
4y2 – 12y + 9
Factorise the following, using the identity a2 – 2ab + b2 = (a – b)2.
`9y^2 - 4xy + (4x^2)/9`
If `x - 1/x = 7` then find the value of `x^2 + 1/x^2`.
