Answer:
√40 is an irrational number
Step-by-step explanation:
"An irrational number is a real number that cannot be expressed as a ratio of integers, for example, √ 2 is an irrational number."
Answer:
B is the answer
Step-by-step explanation:
Answer:
<em>The correct option is C.</em>
Step-by-step explanation:
<u>Root Of Complex Numbers</u>
If a complex number is expressed in polar form as
Then the cubic roots of Z are
![\displaystyle Z_1=\left(\sqrt[3]{r},\frac{\theta}{3}\right)](https://tex.z-dn.net/?f=%5Cdisplaystyle%20Z_1%3D%5Cleft%28%5Csqrt%5B3%5D%7Br%7D%2C%5Cfrac%7B%5Ctheta%7D%7B3%7D%5Cright%29)
![\displaystyle Z_2=\left(\sqrt[3]{r},\frac{\theta}{3}+120^o\right)](https://tex.z-dn.net/?f=%5Cdisplaystyle%20Z_2%3D%5Cleft%28%5Csqrt%5B3%5D%7Br%7D%2C%5Cfrac%7B%5Ctheta%7D%7B3%7D%2B120%5Eo%5Cright%29)
![\displaystyle Z_3=\left(\sqrt[3]{r},\frac{\theta}{3}+240^o\right)](https://tex.z-dn.net/?f=%5Cdisplaystyle%20Z_3%3D%5Cleft%28%5Csqrt%5B3%5D%7Br%7D%2C%5Cfrac%7B%5Ctheta%7D%7B3%7D%2B240%5Eo%5Cright%29)
We are given the complex number in rectangular components
Converting to polar form
It's located in the second quadrant, so
The number if polar form is
Its cubic roots are
![\displaystyle Z_1=\left(\sqrt[3]{2},\frac{120^o}{3}\right)=\left(\sqrt[3]{2},40^o\right)](https://tex.z-dn.net/?f=%5Cdisplaystyle%20Z_1%3D%5Cleft%28%5Csqrt%5B3%5D%7B2%7D%2C%5Cfrac%7B120%5Eo%7D%7B3%7D%5Cright%29%3D%5Cleft%28%5Csqrt%5B3%5D%7B2%7D%2C40%5Eo%5Cright%29)
![\displaystyle Z_2=\left(\sqrt[3]{2},40^o+120^o\right)=\left(\sqrt[3]{2},160^o\right)](https://tex.z-dn.net/?f=%5Cdisplaystyle%20Z_2%3D%5Cleft%28%5Csqrt%5B3%5D%7B2%7D%2C40%5Eo%2B120%5Eo%5Cright%29%3D%5Cleft%28%5Csqrt%5B3%5D%7B2%7D%2C160%5Eo%5Cright%29)
![\displaystyle Z_3=\left(\sqrt[3]{2},40^o+240^o\right)=\left(\sqrt[3]{2},280^o\right)](https://tex.z-dn.net/?f=%5Cdisplaystyle%20Z_3%3D%5Cleft%28%5Csqrt%5B3%5D%7B2%7D%2C40%5Eo%2B240%5Eo%5Cright%29%3D%5Cleft%28%5Csqrt%5B3%5D%7B2%7D%2C280%5Eo%5Cright%29)
Converting the first solution to rectangular coordinates
![z_1=\sqrt[3]{2}(\ cos40^o+i\ sin40^o)](https://tex.z-dn.net/?f=z_1%3D%5Csqrt%5B3%5D%7B2%7D%28%5C%20cos40%5Eo%2Bi%5C%20sin40%5Eo%29)
The correct option is C.
This is the concept of algebra. Given that Holly has 30 pencils, the total number of pencils that Holly remained with after she gave her friends 6 pencils are:
Total=30-6=24 pencils
The fraction of pencils that need to be sharpened is 3/8
The number of pencils represented by this fraction will be:
(fraction of un-sharpened pencils)×(total number of remaining pencils)
3/8×24
=9 pencils
therefore we conclude that 9 pencils are not sharpened.
