Answer:
4.5 mph or 9/2 mph
Step-by-step explanation:
Let x be the rate of the current
Formula: Distance = rate x time
where rate upstream =(12-x) and time =2 hours
15=(12-x)(2)
15=24–2x
2x=24–15
2x= 9
x=9/2=4.5 miles per hour (rate of current)
D/dx ( cos (4x)) = - sin (4x) · d/dx ( 4x) = - 4 sin (4x)
Answer:
d
Step-by-step explanation:
its a triangle all sides are equal. so it would be d-60 degrees