x - [x - {x - (x + 1)}] এর মান কত?
A
x + 1
B
- 1
C
1
D
x - 1
উত্তরের বিবরণ
প্রশ্ন: x - [x - {x - (x + 1)}] এর মান কত?
সমাধান:
x - [x - {x - (x + 1)}]
= x - [x - {x - x - 1}]
= x - [x - {- 1}]
= x - [x + 1]
=x - x - 1
= - 1
0
Updated: 4 months ago
α and β are
the roots of 5x2 + 3x + 1 = 0 then,
the value of (1/α) + (1/β) is-
Created: 1 month ago
A
2
B
- 1
C
5
D
- 3
Question: α and β are the roots of 5x2 + 3x + 1 = 0 then, the value of (1/α) + (1/β) is-
Solution:
Here,
5x2 + 3x + 1 = 0
where, a = 5, b = 6 and c = 1
∴ α + β = - (b/a) = - 3/5
and αβ = c/a = 1/5
∴ (1/α) + (1/β)
= (β + α)/αβ
= {- (3/5)}/(1/5)
= - 3
0
Updated: 6 days ago
x2 - 3x + 1 = 0 হলে (x2 - 1/x2) এর মান -
Created: 2 months ago
A
5√3
B
3√5
C
4√5
D
6√5
প্রশ্ন: x2 - 3x + 1 = 0 হলে (x2 - 1/x2) এর মান-
সমাধান:
x2 - 3x + 1 = 0
⇒ x2 + 1 = 3x
⇒ (x2 + 1)/x = (3x)/x
∴ x + 1/x = 3
আমরা জানি,
(x - 1/x)2 = (x + 1/x)2 - 4.x.(1/x)
⇒ (x - 1/x)2 = (3)2 - 4
⇒ (x - 1/x)2 = 9 - 4
⇒ (x - 1/x)2 = 5
∴ x - 1/x = √5
x2 - 1/x2 = (x)2 - (1/x)2
= (x + 1/x)(x - 1/x)
= 3√5
0
Updated: 2 months ago
What is the
ratio of one-fourth of 9/20 and three-fourths of the same number?
Created: 1 month ago
A
1 : 2
B
3 : 2
C
1 : 3
D
2 : 5
Question: What is the ratio of one-fourth of 9/20 and three-fourths of the same number?
Solution:
one-fourth of 9/20 is {(1/4) × (9/20)} = 9/80
three-fourth of 9/20 is {(3/4) × (9/20)} = 27/80
∴ ratio = 9/80 : 27/80 = 9 : 27 = 1 : 3
0
Updated: 6 days ago
