Answer:
a. cosθ = ¹/₂[e^jθ + e^(-jθ)] b. sinθ = ¹/₂[e^jθ - e^(-jθ)]
Step-by-step explanation:
a.We know that
e^jθ = cosθ + jsinθ and
e^(-jθ) = cosθ - jsinθ
Adding both equations, we have
e^jθ = cosθ + jsinθ
+
e^(-jθ) = cosθ - jsinθ
e^jθ + e^(-jθ) = cosθ + cosθ + jsinθ - jsinθ
Simplifying, we have
e^jθ + e^(-jθ) = 2cosθ
dividing through by 2 we have
cosθ = ¹/₂[e^jθ + e^(-jθ)]
b. We know that
e^jθ = cosθ + jsinθ and
e^(-jθ) = cosθ - jsinθ
Subtracting both equations, we have
e^jθ = cosθ + jsinθ
-
e^(-jθ) = cosθ - jsinθ
e^jθ + e^(-jθ) = cosθ - cosθ + jsinθ - (-jsinθ)
Simplifying, we have
e^jθ - e^(-jθ) = 2jsinθ
dividing through by 2 we have
sinθ = ¹/₂[e^jθ - e^(-jθ)]
First we look for the angle of the vector, which will be given by:
tan (x) = (- 2/3)
Clearing x we have:
x = ATAN (-2/3) = - 33.69 degrees.
Which means that the angle is 33.69 degrees measured clockwise from the x axis.
Equivalently the angle is
360-33.69 = 326.31 degrees
326.31 degrees measured counterclockwise from the x axis.
The vector is then:
v = 10 (cos (326.31) i + sin (326.31) j)
answer
v = 10 (cos (326.31) i + sin (326.31) j)
Answer: 
Step-by-step explanation:
<em>Area of trapezium = </em>
2X = 2 + 2 = 4 cm
2Z = 5 + 5 = 10 cm
Y = 5 cm
|
|--------> 35 
