Advertisements
Advertisements
Question
Simplify (2x +5)2 − (2x − 5)2
Advertisements
Solution
(2x +5)2 − (2x − 5)2 = (2x)2 + 2(2x) (5) + (5)2 − [(2x)2 − 2(2x) (5) + (5)2]
[(a − b)2 = a2 − 2ab + b2]
[(a + b)2 = a2 + 2ab + b2]
= 4x2 + 20x + 25 − [4x2 − 20x + 25]
= 4x2 + 20x + 25 − 4x2 + 20x − 25 = 40x
APPEARS IN
RELATED QUESTIONS
Use a suitable identity to get the following products.
(2y + 5) (2y + 5)
Find the following squares by suing the identities
(xy + 3z)2
Find the following squares by suing the identities.
(2xy + 5y)2
Using identities, evaluate 1.05 × 9.5
Which of the options given below is the square of the binomial `(8-1/"x")`?
Use the formula to find the value.
54 × 46
Expand (3m + 5)2
Expand the following square, using suitable identities
(mn + 3p)2
Show that (x + 2y)2 – (x – 2y)2 = 8xy
Factorise the following, using the identity a2 + 2ab + b2 = (a + b)2.
x2 + 14x + 49
