Advertisements
Advertisements
Question
Use the direct method to evaluate :
(3b−1) (3b+1)
Sum
Solution
Note: (a+b) (a−b) = a2 − b2
(3b−1) (3b+1)
= (3b)2 − (1)2
= 9b2 − 1
shaalaa.com
Is there an error in this question or solution?
APPEARS IN
RELATED QUESTIONS
Evaluate the following using identities:
(399)2
Simplify the following:
0.76 x 0.76 - 2 x 0.76 x 0.24 x 0.24 + 0.24
Simplify the following products:
`(m + n/7)^3 (m - n/7)`
If x = 3 and y = − 1, find the values of the following using in identify:
\[\left( \frac{x}{y} - \frac{y}{3} \right) \frac{x^2}{16} + \frac{xy}{12} + \frac{y^2}{9}\]
If \[x - \frac{1}{x} = \frac{15}{4}\], then \[x + \frac{1}{x}\] =
Expand the following:
(a + 3b)2
Simplify by using formula :
(x + y - 3) (x + y + 3)
Evaluate, using (a + b)(a - b)= a2 - b2.
999 x 1001
Simplify:
(x + y - z)2 + (x - y + z)2
Expand the following:
`(1/x + y/3)^3`
