Question

If A = 3i - 4j and B = -i - 4j, calculate the direction of A+B. vectors lesson
a)tan^-1(4) with +x_axis in clock wise
b)tan^-1(4) with -x_axis in clock wise
c)tan^-1(4) with +x_axis in anti clock wise
d) tan^-1(4) with -x_axis in anti clock wise
WITH WHOLE PROCESS
THEN I WILL DETERMINE AS BRAINLIST​

Answer 1

Answer:

a)tan^-1(4) with +x_axis in clock wise

Explanation:

A+B = (3-1)i +(-4-4)j = 2i-8j

direction of A+B = tan⁻¹ $\frac{-8}{2}$ =tan⁻¹ (-4) = -75.96°

+x_axis in clockwise

Answer 2

Answer: Tan⁻¹(4) with +x axis in anticlockwise

Explanation: A= 3i-4j ,B=-i-4j

A+B= 2i-8j

Now we can see in the below diagram, that the resultant A+B vector makes angle Ф with the x axis .

• tan Ф= -(y coordinate /x coordinate) =-(-8/2)

• tanФ=4

• Ф=tan⁻¹(4)

For seeing whether it is clockwise or anticlockwise ,we have to look at the sign in angle whether it is + or - :

• If sign is positive ,then rotation is anticlockwise
• if sign is negative ,then rotation is clockwise