Advertisements
Advertisements
प्रश्न
If a2 + b2 = 74 and ab = 35, then find a + b.
Advertisements
उत्तर
Given, a2 + b2 = 74 and ab = 35
Since, (a + b)2 = a2 + b2 + 2ab ...[Using the identity, (a + b)2 = a2 + b2 + 2ab]
∴ (a + b)2 = 74 + 2 × 35
⇒ (a + b)2 = 144
⇒ `a + b = sqrt(144)` ...[Taking square root]
⇒ a + b = 12 ...[Rejecting – ve sign]
APPEARS IN
संबंधित प्रश्न
Use a suitable identity to get the following products.
(7a − 9b) (7a − 9b)
Simplify (7m − 8n)2 + (7m + 8n)2
Using identities, evaluate (5.2)2
Using (x + a) (x + b) = x2 + (a + b) x + ab, find 5.1 × 5.2
Use the formula to multiply the following.
`(x/5+6)(x/5-6)`
Use the formula to find the value.
54 × 46
Factorise the following using suitable identity
y2 + 20y + 100
Factorise the following, using the identity a2 + 2ab + b2 = (a + b)2.
`9x^2 + 2xy + y^2/9`
Factorise the following.
y2 + 18x + 65
Factorise p4 + q4 + p2q2.
