Answer:
given you are asked to simplify
Step-by-step explanation:
You have to multiply the numerator and denominator by the denominator's conjugate.
The conjugate of a+bi is a-bi.
When you multiply conjugates, you just have to multiply first and last.
(a+bi)(a-bi)
a^2-abi+abi-b^2i^2
a^2+0 -b^2(-1)
a^2+-b^2(-1)
a^2+b^2
See no need to use the whole foil method; the middle terms cancel.
So we are multiplying top and bottom of your fraction by (-3+4i):
So you will have to use the complete foil method for the numerator. Let's do that:
(-3+5i)(-3+4i)
First: (-3)(-3)=9
Outer:: (-3)(4i)=-12i
Inner: (5i)(-3)=-15i
Last: (5i)(4i)=20i^2=20(-1)=-20
--------------------------------------------Combine like terms:
9-20-12i-15i
Simplify:
-11-27i
Now the bottom (-3-4i)(-3+4i):
F(OI)L (we are skipping OI)
First:-3(-3)=9
Last: -4i(4i)=-16i^2=-16(-1)=16
---------------------------------------------Combine like terms:
9+16=25
So our answer is ![\frac{-11-27i}{25}{/tex] unless you want to seprate the fraction too:[tex]\frac{-11}{25}+\frac{-27}{25}i](https://tex.z-dn.net/?f=%5Cfrac%7B-11-27i%7D%7B25%7D%7B%2Ftex%5D%20unless%20you%20want%20to%20seprate%20the%20fraction%20too%3A%3C%2Fp%3E%3Cp%3E%5Btex%5D%5Cfrac%7B-11%7D%7B25%7D%2B%5Cfrac%7B-27%7D%7B25%7Di)
The answer is digit sum method.
Digit sum method is method used to check the sum of sum numbers. If the sum of all of the digits of numbers is equal to the sum of all of the digits of the total sum, then the arithmetic process was correct.
We need to check the sum of <span>104+34+228+877:
</span>104 + 34 + 228 + 877 = 1243
Let's first summarize the digits of individual numbers:
104 *** 1 + 0 + 4 = 5
34 *** 3 + 4 = 7
228 *** 2 + 2 + 8 = 12 *** 1 + 2 = 3
877 *** 8 + 7 + 7 = 22 *** 2 + 2 = 4
Now, let's sum these sums:
5 + 7 + 3 + 4 = 19 *** 1 + 9 = 10 *** 1 + 0 = <u><em>1</em></u>
Then, let's summarize the digits of the total sum:
1243 *** 1 + 2 + 4 + 3 = 10 *** 1 + 0 = <u><em>1</em></u>
Since the sums of the digits on the both sides of equation is 1, than the arithmetic process was correct and the sum of <span>104 + 34 + 228 + 877 is really 1243.</span>
100% of the price = $400
x % of the price = $320
we need to find x
using a proportion
100 : 400 = x : 320
100 * 320 = 400 * x
32000 = 400x
x = 32000 / 400
x = 80
That means the new price is 80% of the previous price.
100% - 80% = 20%
and based on this we can make a conclusion that the discount was 20%
I hope it is clear to you, feel free to ask anything about it :)
Answer:
The answer can be calculated by doing the following steps;
Step-by-step explanation:
Answer:
Step-by-step explanation:
The Hypothesis :
H0 : σ = 10
H1 : σ ≠ 10
The Chisquare statistic, χ² ;
χ² = [(n-1) * s²] ÷ σ²
Sample size, n = 44 ; sample Standard deviation, s = 10.7 ; population standard deviation, σ = 10
χ² = [(44 - 1) * 10.7²] ÷ 10²
χ² = [43 * 114.49] ÷ 100
χ² = [4923.07] ÷ 100
χ² = 49.2307
Using the Pvalue from Chisquare calculator :
degree of freedom, df = n - 1 = 44 - 1 = 43
Pvalue = 0.238
