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.
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)
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)
Sree said:
4 years ago
How 45 came?
(2)
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)
Shilpa sudhan said:
9 years ago
@Joe.
(3R5)^2 = 3 to the power 2 and root 5 to the power 2 root 5 to the power 2 can be written as root 5 into root 5 which is equal to 5 now we get 3^2 * 5 = 45.
(3R5)^2 = 3 to the power 2 and root 5 to the power 2 root 5 to the power 2 can be written as root 5 into root 5 which is equal to 5 now we get 3^2 * 5 = 45.
(1)
Swathi said:
9 years ago
Please solve this question in the easy way of method.
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.
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