Advertisements
Advertisements
Question
Using a2 − b2 = (a + b) (a − b), find 12.12 − 7.92
Advertisements
Solution
12.12 − 7.92 = (12.1 + 7.9) (12.1 − 7.9)
= (20.0) (4.2) = 84
RELATED QUESTIONS
Using identities, evaluate 992
Using (x + a) (x + b) = x2 + (a + b) x + ab, find 103 × 98
Use an expansion formula to find the value.
(1005)2
Use the formula to multiply the following.
(a + 6) (a − 6)
Use a formula to multiply of (4z – 5y)(4z + 5y)
Factorise the following.
x2 + 9x + 20
If p + q = 12 and pq = 22, then find p2 + q2.
Verify the following:
(5x + 8)2 – 160x = (5x – 8)2
Factorise `x^2 + 1/x^2 + 2 - 3x - 3/x`.
Take suitable number of cards given in the adjoining diagram [G(x × x) representing x2, R(x × 1) representing x and Y(1 × 1) representing 1] to factorise the following expressions, by arranging the cards in the form of rectangles:
- 2x2 + 6x + 4
- x2 + 4x + 4.
Factorise 2x2 + 6x + 4 by using the figure.
Calculate the area of figure.
