Incorrect math calculation in lecture 6

[Therealchainman]

I found some incorrect calculations I believe.

lecture 6, slide 26
It gets the answer equal to 2, but if you perform the calculations you will get 2.164. It seems it is treating the input to the sin function as degrees, but it's radians? It is 90 radians from e^4.499. I've searched online and I can't find a reason it would be interpreted as degrees.

This also makes the calculations for slide 27 wrong for the same reason, where it gets the output to be 0 for the derivative, because it gets cos(90) = 0, but yeah I think 90 is in radians and it is not equal to 0.

Please let me know if I'm in the wrong and the error of my ways.

[pbloem]

Hi, the input should indeed be interpreted in degrees. These lectures are for second year BSc students, so giving angles in degrees seemed a bit more intuitive.

The arguments to trigonometric functions can be in degrees or radians. It's up to the author to decide.