00:01
Hello, let's have a look on the question.
00:02
So the points are given to us 7 root 7, negative of 4 and 5.
00:08
So we need to convert these into cylindrical coordinates.
00:11
So x is equal to 7 root 7, y is equal to minus of 4 and z is equals to 5.
00:19
So in cylindrical coordinates, in cylindrical coordinates we have x is equal to r cos theta, y is equal to r sine theta and z is equal to z as it is now if we square x -square is equal to r square cos square theta and y -square is equal to r square sine square theta now if we add both these terms x -square plus y -square so x -square plus y -square is equal to taking r -square common into cos square theta plus sine square theta.
01:03
So the value of cos square theta plus sine square theta is 1.
01:06
So x square plus y square is equal to r square.
01:10
It implies that the value of r is equal to under root of x square plus y square.
01:15
Now the value of x was 7 root 7 and the value of y was minus 4.
01:23
So this will be equal to 49 into 7 plus 16.
01:33
So the final value is equal to under root of t -59.
01:38
So this is the value of x square plus y square...