Answer:
Step-by-step explanation:
- Speed in one direction = 40 km/h
- Speed on return = x
- Average speed = 60 km/h
Let the distance be d
<u>Average speed </u>
- 2d/(d/40 + d/x) = 60
- d/40 + d/x = 2d/60
- 1/40 + 1/x = 1/30
- 1/x = 1/30 - 1/40
- 1/x = (4-3)/120
- 1/x = 1/120
- x = 120 km/h
Answer: 8
Step-by-step explanation:
Answer:
i think the answer is 10-11 but i'm not sure i'm sorry
Step-by-step explanation:
Answer:
x = ±
- 2
Step-by-step explanation:
x² + 4x = 4
to complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(2)x + 4 = 4 + 4
(x + 2)² = 8 ( take square root of both sides )
x + 2 = ±
( subtract 2 from both sides )
x = ±
- 2
Dy/dx (2x⁵ y³ - 4y/x)
dy/dx (2y³ x⁵ - 4y/x)
dy/dx ( 2y³ x⁵ ) - dy/dx (4y/x)
= 2y³ 5x⁴ - (-4y × 1/x²)
=
10x⁶ y³ + 4y
-------------------
x²