Answer:
65625/4(x^5)(y²)
Step-by-step explanation:
Using binomial expansion
Formula: (n k) (a^k)(b ^(n-k))
Where (n k) represents n combination of k (nCk)
From the question k = 5 (i.e. 5th term)
n = 7 (power of expression)
a = 5x
b = -y/2
....................
Solving nCk
n = 7
k = 5
nCk = 7C5
= 7!/(5!2!) ------ Expand Expression
=7 * 6 * 5! /(5! * 2*1)
= 7*6/2
= 21 ------
.........................
Solving (a^k) (b^(n-k))
a = 5x
b = -y/2
k = 5
n = 7
Substituting these values in the expression
(5x)^5 * (-y/2)^(7-5)
= (3125x^5) * (-y/2)²
= 3125x^5 * y²/4
= (3125x^5)(y²)/4
------------------------------------
Multiplying the two expression above
21 * (3125x^5)(y²)/4
= 65625/4(x^5)(y²)
-37842
-------------
2,376
Then, round 2,376 to the nearest thousands
2,376 -> 2,000
Answer:
I think PR = 20 but I'm not sure
Answer: $12000 was invested at 7% while $8000 was invested at 9%.
Step-by-step explanation:
Based on the information given in the question, let the amount that was invested at 7% be n.
Therefore,
0.07n + 0.09(20000 - n) = 1560
0.07n + 1800 - 0.09n = 1560
-0.02n = 1560 - 1800
-0.02n = -240
n = 240/0.02
n = 120
Therefore, $12000 was invested at 7% while $8000 was invested at 9%.
Let’s make an equation
Let’s say x = amount of years after
Smith = 8, mother = 42
3(8 + x) = 42 + x
24 + 3x = 42 + x
2x = 18, x = 9
Solution: after 9 years
