Advertisements
Advertisements
प्रश्न
a2 – b2 is equal to ______.
पर्याय
(a – b)2
(a – b)(a – b)
(a + b)(a – b)
(a + b)(a + b)
उत्तर
a2 – b2 is equal to (a + b)(a – b).
Explanation:
a. (a – b)2 = a2 – 2ab + b2
b. (a – b)(a – b) = (a – b)2 = a2 – 2ab + b2
c. (a + b)(a – b) = a(a – b) + b(a – b) + b(a – b)
= a2 – ab + ba – b2 ...[∵ ab = ba]
= a2 – b2
d. (a + b)(a + b) = (a + b)2 = a2 + 2ab + b2
APPEARS IN
संबंधित प्रश्न
Expand `("x"-2/"x")^2`
Expand `("a"-1/"a")^2`
Simplify: (a + b)2 – (a – b)2
Factorise the following, using the identity a2 – 2ab + b2 = (a – b)2.
x2 – 8x + 16
Factorise the following.
y2 – 2y – 15
Factorise the following.
p2 – 13p – 30
The curved surface area of a cylinder is 2π(y2 – 7y + 12) and its radius is (y – 3). Find the height of the cylinder (C.S.A. of cylinder = 2πrh).
If m – n = 16 and m2 + n2 = 400, then find mn.
Verify the following:
(a – b)(a – b)(a – b) = a3 – 3a2b + 3ab2 – b3
Subtract b(b2 + b – 7) + 5 from 3b2 – 8 and find the value of expression obtained for b = – 3.
