15-4 = 11
11 x 2 = 22
22 + 2/3 = 68/3
Answer:
Following are the responses to the given question:
Step-by-step explanation:
Mean Absolute Deviation MAD
Mean squared error
linear trend equation is 

Naive method

Please find the attached file.
Answer:
The complex number in the form of a + b i is 3/2 + i √3/2
Step-by-step explanation:
* Lets revise the complex number in Cartesian form and polar form
- The complex number in the Cartesian form is a + bi
-The complex number in the polar form is r(cosФ + i sinФ)
* Lets revise how we can find one from the other
- r² = a² + b²
- tanФ = b/a
* Now lets solve the problem
∵ z = 3(cos 60° + i sin 60°)
∴ r = 3 and Ф = 60°
∵ cos 60° = 1/2
∵ sin 60 = √3/2
- Substitute these values in z
∴ z = 3(1/2 + i √3/2) ⇒ open the bracket
∴ z = 3/2 + i √3/2
* The complex number in the form of a + b i is 3/2 + i √3/2