Answer:
c. Cos θ = [tex]A_{x}[/tex] / [tex]\sqrt{(A_{x} ^{2} + A_{y} ^{2}) }[/tex]
Explanation:
A vector is any quantity that has both magnitude and direction. The given vector A has components [tex]A_{x}[/tex] and [tex]A_{y}[/tex], and makes angle θ with +x axis.
Thus;
Resultant of the vector, A = [tex]\sqrt{(A_{x} ^{2} + A_{y} ^{2}) }[/tex]
Therefore, the components, angle and resultant of vector A can be represented in magnitude and direction by the three sides of a right angled triangle.
Applying the appropriate trigonometric function to the triangle for vector A, we have;
Cos θ = [tex]A_{x}[/tex] ÷ [tex]\sqrt{(A_{x} ^{2} + A_{y} ^{2}) }[/tex]
⇒ Cos θ = [tex]A_{x}[/tex] / [tex]\sqrt{(A_{x} ^{2} + A_{y} ^{2}) }[/tex]
The correct option is C.
