Advertisements
Advertisements
प्रश्न
Use suitable identity to find the following product:
(x + 8) (x – 10)
Advertisements
उत्तर
By using the identity (x + a)(x + b) = x2 + (a + b)x + ab,
(x + 8)(x – 10) = x2 + (8 – 10)x (8)(–10)
= x2 + (–2)x + (–80)
= x2 – 2x – 80
APPEARS IN
संबंधित प्रश्न
Factorise the following using appropriate identity:
4y2 – 4y + 1
If x + y + z = 0, show that x3 + y3 + z3 = 3xyz.
If `x + 1/x = sqrt5`, find the value of `x^2 + 1/x^2` and `x^4 + 1/x^4`
If \[a^2 + \frac{1}{a^2} = 102\] , find the value of \[a - \frac{1}{a}\].
If \[x^3 + \frac{1}{x^3} = 110\], then \[x + \frac{1}{x} =\]
\[\frac{( a^2 - b^2 )^3 + ( b^2 - c^2 )^3 + ( c^2 - a^2 )^3}{(a - b )^3 + (b - c )^3 + (c - a )^3} =\]
Evaluate `(a/[2b] + [2b]/a )^2 - ( a/[2b] - [2b]/a)^2 - 4`.
If x + y = `7/2 "and xy" =5/2`; find: x - y and x2 - y2
Evaluate: (4 − ab) (8 + ab)
Evaluate: (1.6x + 0.7y) (1.6x − 0.7y)
Evaluate the following without multiplying:
(95)2
Evaluate, using (a + b)(a - b)= a2 - b2.
399 x 401
If x + y = 9, xy = 20
find: x2 - y2.
If m - n = 0.9 and mn = 0.36, find:
m + n
If p2 + q2 + r2 = 82 and pq + qr + pr = 18; find p + q + r.
If `x^2 + (1)/x^2 = 18`; find : `x - (1)/x`
If `"r" - (1)/"r" = 4`; find: `"r"^2 + (1)/"r"^2`
If `"a" + (1)/"a" = 2`, then show that `"a"^2 + (1)/"a"^2 = "a"^3 + (1)/"a"^3 = "a"^4 + (1)/"a"^4`
If a + b + c = 0, then a3 + b3 + c3 is equal to ______.
Give possible expressions for the length and breadth of the rectangle whose area is given by 4a2 + 4a – 3.
