Advertisements
Advertisements
प्रश्न
If x+ y - z = 4 and x2 + y2 + z2 = 30, then find the value of xy - yz - zx.
योग
Advertisements
उत्तर
x + y - z = 4 and x2 + y2 + z2 = 30
Since ( x + y - z)2 = x2 + y2 + z2 + 2( xy - yz - zx ), we have
(4)2 = 30 + 2( xy - yz - zx )
⇒ 16 = 30 + 2( xy - yz - zx )
⇒ 2( xy - yz - zx ) = -14
⇒ xy - yz - zx = `-14/2` = -7
∴ xy - yz - zx = -7
shaalaa.com
Expansion of Formula
क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
APPEARS IN
संबंधित प्रश्न
Expand : ( x + 8 ) ( x + 10 )
Expand : ( x - 8 )( x - 10 )
Expand: `( 2x - 1/x )( 3x + 2/x )`
Expand : ( x + y - z )2
Expand : ( x - 2y + 2 )2
Expand : ( 5a - 3b + c )2
If a2 + b2 + c2 = 50 and ab + bc + ca = 47, find a + b + c.
The difference between two positive numbers is 4 and the difference between their cubes is 316.
Find : Their product
Find the value of 'a': 9x2 + (7a - 5)x + 25 = (3x + 5)2
If x = `1/[ 5 - x ] "and x ≠ 5 find "x^3 + 1/x^3`
