00:01
Hi guys, this problem you are given that f of x and y is equal to sex over 7 times x squared plus xy over 2.
00:13
This is for x more than 0 and less than 1 and y more than 0 and less than 2.
00:23
Okay, so now we have integration over x from 0 to 1.
00:32
Then integration from 0 to 2.
00:35
For f of x, d .x, so this is 6 over 7, x squared plus xy over 2, d .y, d .x.
00:48
This is equal to 1.
00:50
Okay.
00:53
So, this is 6 over 7 times integration from 0 to 1.
00:59
For x squared y plus x over 2 times y squared over 2 and then we have the limits to and 0 then we integrate relative to x okay so this is 1 so this is 6 over 7 times 2 x cube over 3 plus x squared over 2 and then we have the limits 1 and 0 this is equal to 1 so this is 6 over 7 times 7 over 6 this is true since the true function can be written as double integration over x and y is equal to 1 so now we need to find the f of x this is integration over y from 0 to 2 for 6 over 7 times x squared plus xy over 2, d .y.
02:12
So this is 6 over 7 times 2x squared plus x.
02:20
Okay.
02:22
So probability of x more than y, this is integration from x to 0 to 1.
02:30
Then integration over y from 0 to x.
02:34
First x over 7 times x squared plus xy over 2 plus xy over 2.
02:40
D -y -d -x so in party we need to find this probability okay so here it's x -axis and here the y -axis so when y is equal to 2 and x is equal to 1 okay so here we have a rectangle that's high of 2 and what's of 1 so um this is all 0 .5 and this is 1.
03:16
Okay.
03:17
So this is where x less than y.
03:28
Okay.
03:29
So this probability is just 6 over 7.
03:34
It's an integration from 0 to 1.
03:37
4 x squared y plus xy squared over 4.
03:43
Okay.
03:44
Then we have the limits x and 0.
03:47
Then t x.
03:49
Okay.
03:50
So, um, this is 6 over 7 times integration from 0 to 1, 4, 5 x cubed over 4, the x.
03:59
So this is 30 over 28 times x power 4 over 4.
04:08
And we have the limits 1 and 0.
04:10
So this probability is 0 .2, 6, 7, 8.
04:16
Okay, and part d, we have a plot for x and y.
04:24
So this is x is equal to 1.
04:31
Here is 0 .5...