Answer:
The unit vector u is (-5/√29) i - (2/√29) j
Step-by-step explanation:
* Lets revise the meaning of unit vector
- The unit vector is the vector ÷ the magnitude of the vector
- If the vector w = xi + yj
- Its magnitude IwI = √(x² + y²) ⇒ the length of the vector w
- The unit vector u in the direction of w is u = w/IwI
- The unit vector u = (xi + yj)/√(x² + y²)
- The unit vector u = [x/√(x² + y²)] i + [y/√(x² + y²)] j
* Now lets solve the problem
∵ v = -5i - 2j
∴ IvI = √[(-5)² +(-2)²] = √[25 + 4] = √29
- The unit vector u = v/IvI
∴ u = (-5i - 2j)/√29 ⇒ spilt the terms
∴ u = (-5/√29) i - (2/√29) j
* The unit vector u is (-5/√29) i - (2/√29) j
Answer: The value of x= 18
Step-by-step explanation:
Given: In triangle EFG, angle E equals 8x-16, angle F equals x+8, and angle G equals 2x-10.
The sum of all angles of a triangle is 180°.
Therefore, in triangle EFG
∠E + ∠F +∠G= 180°
⇒ 8x-16 +x+8+ 2x-10 = 180
⇒ 11x-18= 180
⇒ 11x = 180+18
⇒11x=198
⇒ x= 18 [Divide both sides by 11]
Hence, the value of x= 18
Answer:
The length of AB is 7.45 units.
Step-by-step explanation:
You can find the length of AB using Cosine Rule, cosθ = adj./hypo. :
θ = 20°
adj. = 7 units
hypo. = AB
cos 20° = 7/AB
AB = 7/cos 20°
= 7.45 units (3s.f)
