You take out the biggest factor of 9 and 36 which is 9c^2. The factors both have the c variable in common so you take the least exponent and put it with the gcf.
9c^2(c^2+4)
-x^2 + 9 - 3x^2 - 11x + 4
-4x^2 - 11x + 13
Answer:
Yes, we can conclude that the population standard deviation of TV watching times for teenagers is less than 2.66
Step-by-step explanation:
H0 : σ² = 2.66²
H1 : σ² < 2.66²
X²c = (n - 1)*s² ÷ σ²
sample size, n = 40
Sample standard deviation, s = 1.9
X²c = ((40 - 1) * 1.9²) ÷ 2.66²
X²c = 140.79 ÷ 7.0756
X²c = 19.897
Using a confidence level of 95%
Degree of freedom, df = n - 1 ; df = 40 - 1 = 39
The critical value using the chi distribution table is 25.6954
Comparing the test statistic with the critical value :
19.897 < 25.6954
Test statistic < Critical value ; Reject the Null
Hence, we can conclude that the population standard deviation of TV watching times for teenagers is less than 2.66
i don't understand, what is it asking for here?
Answer:
So, option A is correct.
Step-by-step explanation:
To find the inverse of the matrix, the formula is:

Inverse of the matrix exists if |A| does not equal to 0
|A| = 7 * 9 -( -2 * -10)
|A| = 63 - 20
|A| = 43
AS |A| ≠ 0
so inverse exist.
now finding Adj A
= ![\left[\begin{array}{cc}9&2\\10&7\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D9%262%5C%5C10%267%5Cend%7Barray%7D%5Cright%5D)
![\left[\begin{array}{cc}9/43&2/43\\10/43&7/43\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D9%2F43%262%2F43%5C%5C10%2F43%267%2F43%5Cend%7Barray%7D%5Cright%5D)
So, option A is correct.