(A-B)²=A²-2AB+B²
verify it
Answers
Answer:
Step-by-step explanation:
This called the perfect square formula
A = 6
B = 5
(6 - 5)^2 = 1
6^2 - 2 x 6 x 5 + 5^2 = 1
This formula works for all integers
Topic
Algebraic Identities
To Verify
( a - b )² = a² - 2ab + b²
Solution
Technique 1
To verify the identity,
- Take different values of a and b
- Check whether these values satisfy the identity or not.
Now,
Taking a = 5 and b = 1
Solving LHS,
( 5 - 1 )²
4²
16
Solving RHS,
5² - 2( 5 )( 1 ) + 1²
25 - 10 + 1
26 - 10
16
Given identity is true for these values.
Now,
Take a = 8 and b = 2
Solving LHS,
( 8 - 2 )²
6²
36
Solving RHS,
8² - 2(8)(2) + 2²
64 - 32 + 4
68 - 32
36
Given identity is true for these values also.
So, we can say that this identity is true for all different values of a and b.
Hence, verified.
Technique 2
We can use simple algebraic multiplication.
( a - b )² = ( a - b ) × ( a - b )
Now, we will do multiplication
( a - b ) × ( a - b )
a( a - b ) - b( a - b )
a² - ab - ba + b²
a² - 2ab + b²
( Note: ab = ba )
So, we can write
( a - b )² = a² - 2ab + b²
Hence, verified.