Aptitude - Simplification - Discussion
Discussion Forum : Simplification - General Questions (Q.No. 4)
4.
If a - b = 3 and a2 + b2 = 29, find the value of ab.
Answer: Option
Explanation:
2ab = (a2 + b2) - (a - b)2
= 29 - 9 = 20
ab = 10.
Discussion:
107 comments Page 8 of 11.
Raj said:
9 years ago
If a + 1/a = 4, then a^2 + 1/a^2 = ?
Rushah said:
9 years ago
@Antara.
It's very easy. Remove brackets and multiply you got 2ab.
It's very easy. Remove brackets and multiply you got 2ab.
Antara chatterjee said:
9 years ago
a2 + b 2= 52,and a - b = 2. Then ab?
Anyone solve this problem.
Anyone solve this problem.
Amit said:
9 years ago
It's so easy Easy method.
Given.
a - b = 3 and a * a - b * b = 3,
So,
a = 5 and b = 2.
Then,
ab = 5 * 2 = 10.
Given.
a - b = 3 and a * a - b * b = 3,
So,
a = 5 and b = 2.
Then,
ab = 5 * 2 = 10.
Hepinder happy said:
9 years ago
@Saad.
a^2 - b^2 = (a+b)(a-b) we have given a^2 - b^2 = 30 and a - b= 5.
Then (a + b)(a - b) = 30.
a + b = 30/(a -b).
a + b = 30/5.
a + b = 6
Solving 1 & 2 we get,
2a = 11.
a = 11/2 then ab =11/4 --> Answer.
a^2 - b^2 = (a+b)(a-b) we have given a^2 - b^2 = 30 and a - b= 5.
Then (a + b)(a - b) = 30.
a + b = 30/(a -b).
a + b = 30/5.
a + b = 6
Solving 1 & 2 we get,
2a = 11.
a = 11/2 then ab =11/4 --> Answer.
Saad said:
9 years ago
If a2 - b2 = 30 and a - b = 5, then find the value of ab?
SMRUTI RANJAN said:
9 years ago
If a2 - b2 = 37, then a2 + b2 = ? Please explain?
Jisha said:
10 years ago
@Harisha can you explain your question?
Harisha said:
10 years ago
Solve the problem if a+1/a-2=4. Find the value of (a-2)^2+(1/a-2)^2?
Manjunatha dv said:
1 decade ago
a-b = 3.
5-2 = 3.
a^2+b^2 = 29.
5^2+2^2 = 29.
Answer = 5*2 = 29.
5-2 = 3.
a^2+b^2 = 29.
5^2+2^2 = 29.
Answer = 5*2 = 29.
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