Advertisements
Advertisements
प्रश्न
Simplify (2x – 5y)3 – (2x + 5y)3.
Advertisements
उत्तर
(2x – 5y)3 – (2x + 5y)3 = [(2x)3 – (5y)3 – 3(2x)(5y)(2x – 5y)] – [(2x)3 + (5y)3 + 3(2x)(5y)(2x + 5y)] ...[Using identity, (a – b)3 = a3 – b3 – 3ab and (a + b)3 = a3 + b3 + 3ab]
= (2x)3 – (5y)3 – 30xy(2x – 5y) – (2x)3 – (5y)3 – 30xy(2x + 5y)
= –2(5y)3 – 30xy(2x – 5y + 2x + 5y)
= –2 × 125y3 – 30xy(4x)
= –250y3 – 120x2y
APPEARS IN
संबंधित प्रश्न
Evaluate the following using suitable identity:
(99)3
Verify:
x3 – y3 = (x – y) (x2 + xy + y2)
Without actually calculating the cubes, find the value of the following:
(28)3 + (–15)3 + (–13)3
Simplify the following:
322 x 322 - 2 x 322 x 22 + 22 x 22
If a2 + b2 + c2 = 16 and ab + bc + ca = 10, find the value of a + b + c.
Evaluate of the following:
`(10.4)^3`
If a + b = 8 and ab = 6, find the value of a3 + b3
If a + b = 6 and ab = 20, find the value of a3 − b3
Find the following product:
(4x − 3y + 2z) (16x2 + 9y2 + 4z2 + 12xy + 6yz − 8zx)
If \[x + \frac{1}{x} = 3\] then find the value of \[x^6 + \frac{1}{x^6}\].
75 × 75 + 2 × 75 × 25 + 25 × 25 is equal to
Use the direct method to evaluate :
(xy+4) (xy−4)
Evaluate: (2 − z) (15 − z)
Expand the following:
(a + 4) (a + 7)
Simplify by using formula :
(x + y - 3) (x + y + 3)
Evaluate, using (a + b)(a - b)= a2 - b2.
4.9 x 5.1
If `"a" + (1)/"a" = 2`, then show that `"a"^2 + (1)/"a"^2 = "a"^3 + (1)/"a"^3 = "a"^4 + (1)/"a"^4`
Factorise the following:
9y2 – 66yz + 121z2
Expand the following:
(3a – 5b – c)2
