scaryshark09
∞∆ who let 'em cook dis long ∆∞
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the derivative is 6costsint and yes i know that its negative when you sub in, but that doesn't mean that the speed is decreasing, that just means that the speed is in the negative directionfor 9 if u differentiate it you get 6cost and then sub 5pi/6 in that it's negative - therefore D
what's the answer to 4?
i disagree.Like @user18181818 said, the derivative is 6cosxsinx and if you substitute t=5π/6, you get -2.5980.... which is decreasing speed since the gradient is negative, thus, D.
just draw graphically and then there are 2 points of intersectionhow do u do 4
that just means the speed is in the negative direction, but that doesnt matter for thisn question as speed is a scalar quantity. you have to differentiate again to find the gradiant of the speed to find out if its increasing or decreasing. and this is positive. so shouldnt the answer be C?Like @user18181818 said, the derivative is 6cosxsinx and if you substitute t=5π/6, you get -2.5980.... which is decreasing speed since the gradient is negative, thus, D.
can you explain 9
As you said you have to differentiate again. This gives you the acceleration which is positive, also as you said. A positive acceleration means the particle is being pushed to the right, while a negative velocity means the particle is moving to the left. Since it is moving to the left but being pushed to the right, it is slowing downthat just means the speed is in the negative direction, but that doesnt matter for thisn question as speed is a scalar quantity. you have to differentiate again to find the gradiant of the speed to find out if its increasing or decreasing. and this is positive. so shouldnt the answer be C?
how many papers r u doing and which questions and wher eu getting the q fromm
read the title of this threadwher eu getting the q fromm
It’s the same deal as last time, for each possibility you also have an identical possibility with the groups swapped, so in order to cancel this out you halve it. the reason part 2 is different is because there are 2 people who have been fixed in one group and hence there is never an identical possibility where everyone’s in the other group because they’re never in the other group themselvescan someone explain when and when not to divide by 2?
and why do you even need to divide by 2?
if theres 12 people in a line, and you choose 6, how is this double the answer? @carrotsss