Answer:
D) 24m, 300o
Step-by-step explanation:
The vector A has magnitude of 12 m and it makes 120 degree with + ve x axis
So it can be represented by the vector as follows
A = 12 Cos 120 i + 12 sin 120 j
vector 2A = 24 Cos 120 i + 24 sin 120 j
- 2A = - 24 Cos 120 i - 24 sin 120 j
= 24 Cos ( 180 -120 ) - 24 sin ( 180 -120)
= 24 Cos 60 - 24 sin 60
= 24 Cos ( 360 - 60 ) + 24 sin ( 360 -60 )
= 24 Cos 300 + 24 sin 300
It represents a vector having magnitude of 24 and making 300 degree with + ve x- axes in anticlockwise direction.