Aptitude - Square Root and Cube Root - Discussion
Discussion Forum : Square Root and Cube Root - General Questions (Q.No. 9)
9.
The square root of (7 + 35) (7 - 35) is
Answer: Option
Explanation:
| (7 + 35)(7 - 35) | = | (7)2 - (35)2 | = 49 - 45 = 4 = 2. |
Discussion:
24 comments Page 1 of 3.
Devendra said:
2 years ago
To find the square root of the expression (7 + 3√5) (7 - 3√5), we can simplify it using the difference of squares formula.
Let's denote the expression as A = (7 + 3√5) (7 - 3√5).
Using the difference of squares formula, we have:
A = (7 + 3√5) (7 - 3√5)
= (7)^2 - (3√5)^2,
= 49 - 9(√5)^2,
= 49 - 9(5),
= 49 - 45,
= 4.
Therefore, the √ of (7 + 3√5) (7 - 3√5) is √4 = 2.
Let's denote the expression as A = (7 + 3√5) (7 - 3√5).
Using the difference of squares formula, we have:
A = (7 + 3√5) (7 - 3√5)
= (7)^2 - (3√5)^2,
= 49 - 9(√5)^2,
= 49 - 9(5),
= 49 - 45,
= 4.
Therefore, the √ of (7 + 3√5) (7 - 3√5) is √4 = 2.
(2)
Ranjith Ragava said:
3 years ago
(7+3√5)(7-3√5).
(a+b)(a-b)=a^2-b^2,
= (7)^2-(3√5)^2,
= (49)-(3^2√5^2),
= 49-(9)(5),
= 49-45,
= 4.
(a+b)(a-b)=a^2-b^2,
= (7)^2-(3√5)^2,
= (49)-(3^2√5^2),
= 49-(9)(5),
= 49-45,
= 4.
(3)
Shahil Solanki said:
3 years ago
@Sweety and @Sree
(3√5)^2.
= 3^2 *(√5)^2,
= 9 * 5,
= 45.
(3√5)^2.
= 3^2 *(√5)^2,
= 9 * 5,
= 45.
(1)
Sree said:
4 years ago
How 45 came?
(2)
Sweety said:
6 years ago
How come 45?
Sonam said:
6 years ago
Sir, how come 45? please tell me.
Priya said:
7 years ago
@All.
It is mentioned that the square root of (find the square root of a given item), by solving we will get 4. Take the square root of 4 the answer is 2.
It is mentioned that the square root of (find the square root of a given item), by solving we will get 4. Take the square root of 4 the answer is 2.
Sreekanth said:
8 years ago
Here square root is already there.
So, a+b * a-b = a2-b2. so, square root a2-b2. So answer is 2 only.
So, a+b * a-b = a2-b2. so, square root a2-b2. So answer is 2 only.
Rafeeq said:
8 years ago
In the question, it is mentioned Square root of....
And the given no is (a+b)(a-b) form. After solving using this formula you will get 4 as the answer. Now note the question, it is mentioned as the square root of. Hence we have to take the whole square root. Hope my answer will be understood by everyone.
And the given no is (a+b)(a-b) form. After solving using this formula you will get 4 as the answer. Now note the question, it is mentioned as the square root of. Hence we have to take the whole square root. Hope my answer will be understood by everyone.
Vidya Channabasava Kabber said:
8 years ago
The answer should be 4. How it is 2. Can you explain?
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