Advertisements
Advertisements
Question
Use the direct method to evaluate :
(2+a) (2−a)
Advertisements
Solution
Note: (a+b) (a−b) = a2 − b2
(2+a) (2−a) = (2)2 − (a)2
= 4 − a2
APPEARS IN
RELATED QUESTIONS
Expand the following, using suitable identity:
`[1/4a-1/2b+1]^2`
If \[x^2 + \frac{1}{x^2}\], find the value of \[x^3 - \frac{1}{x^3}\]
Find the value of 27x3 + 8y3, if 3x + 2y = 14 and xy = 8
Simplify of the following:
If \[x - \frac{1}{x} = \frac{15}{4}\], then \[x + \frac{1}{x}\] =
The difference between two positive numbers is 5 and the sum of their squares is 73. Find the product of these numbers.
Use the direct method to evaluate the following products:
(a – 8) (a + 2)
If `"a"^2 + (1)/"a"^2 = 14`; find the value of `"a" + (1)/"a"`
If `x/y + y/x = -1 (x, y ≠ 0)`, the value of x3 – y3 is ______.
Give possible expressions for the length and breadth of the rectangle whose area is given by 4a2 + 4a – 3.
