যদি x4 - x2 + 1 = 0 হয়, তবে, x3 + 1/x3 = কত?
A
3
B
2
C
1
D
0
উত্তরের বিবরণ
প্রশ্ন: যদি x4 - x2 + 1 = 0 হয়, তবে, x3 + 1/x3 = কত?
সমাধান:
x4 - x2 + 1 = 0
⇒ x4 +1 = x2
⇒ (x4 + 1)/x2 = 1
⇒ x2 + 1/x2 = 1
⇒ (x + 1/x)2 -2.x.1/x =1
∴ x+ (1/x) = √3
x3 + (1/x)3
= {x + (1/x)}3 - 3.x. (1/x) {x + (1/x)}
= (√3)3 - 3. √3
= 3√3 - 3√3
= 0
0
Updated: 1 month ago
log3(9/243) এর
মান কত?
Created: 1 month ago
A
9
B
- 3
C
12
D
81
প্রশ্ন: log3(9/243) এর মান কত?
সমাধান:
= log3(9/243)
= log3(1/27)
= log3(3-3)
= - 3 × log3(3)
= - 3 × 1
= - 3
0
Updated: 1 month ago
যদি a + b = 5 এবং a2 + b2 = 13 হয়, তবে a3 + b3 এর মান কত?
Created: 1 month ago
A
28
B
35
C
65
D
81
প্রশ্ন: যদি a + b = 5 এবং a2 + b2 = 13 হয়, তবে a3 + b3 এর মান কত?
সমাধান:
দেয়া আছে, a + b = 5 এবং a2 + b2 = 13
এখন,
(a + b)2 = a2 + b2 + 2ab
⇒ 52 = 13 + 2ab
⇒ 25 = 13 + 2ab
⇒ 25 - 13 = 2ab
⇒ 12 = 2ab
⇒ ab = 6
∴ a3 + b3 = (a + b)3 - 3ab(a + b)
⇒ a3 + b3 = (5)3 - 3(6)(5)
⇒ a3 + b3 = 125 - 90
∴ a3 + b3 = 35
0
Updated: 1 month ago
If HOUSE = 81521195 and TREE = 201855, then GARDEN will be equal to-
Created: 1 month ago
A
71518414
B
7184514
C
71845141
D
71184514
Question: If HOUSE = 81521195 and TREE = 201855, then GARDEN will be equal to-
Solution:
According to the English alphabet,
HOUSE = 8 15 21 19 5
And,
TREE = 20 18 5 5
Now,
GARDEN = 7 1 18 4 5 14
So the code is- 71184514
∴ GARDEN = 71184514
0
Updated: 1 month ago