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2 / 1 of the car speed is equivalent to the train speed, and the unit "1" is（
Vehicle speed
The unit before the score is one
The speed of a car is one sixth slower than that of a train. What's the unit 1
train
The speed of a train is 180 kilometers per hour. The speed of a car is five ninth that of a train and one ninth that of a jet plane. What is the speed of this jet plane?
Car speed = 180 × 5 / 9 = 100 km / h
Aircraft speed = 100 ÷ 1 / 9 = 900 km / h
The train travels 80 kilometers per hour, and the car is 20.5 kilometers slower than the train. What is the speed of the car? You want to do it
Is the condition that "a car is 20.5 kilometers per hour slower than a train" wrong
This should be done:
The car travels 80-20.5 = 59.5 kilometers per hour
The speed of the car is 59.5 / 80 = 119 / 160 of that of the train
Indefinite integral, simple problem Can the coefficient after d be put in front of the integral number? 1. X2dx of the root sign (x3 power-1) = 1 / 3 of the integral sign, 1dx3 power of the root sign (x3 power-1)? 2. (2 / 3) x power DX of integral sign e = - 3 / 2 integral sign e (- 2 / 3) x power D (- 2 / 3) x? Why, Jenny?
1. D the following coefficient can be placed in front of the integral number!
2. Yes
3. Before you mention the coefficient after D to the integral sign, it is actually the (- 2 / 3) x power DX of the integral sign E
Simple indefinite integral problem How much is ∫ [(1) / (square X of sin)] DX?
Original formula = ∫ CSC ² xdx
=-∫(-csc ² x)dx
=-cotx+C
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