Question

MIT 6.189 Math Module HW 2.3

Answer 1

I was able to get working answers to the math module homework, but I worry I missed some of the spirit of the exercise. For a few of the multadds, I ended up just multiplying by 1, e.g.

angle_test = multadd(1,math.sin(math.pi/4),math.cos(math.pi/4)/2)

Here's a link to 2.3 in its entirety. Would love some feedback.

https://gist.github.com/TomDeBeauchamp/5855418

Answer 2

I didn't see import math there....

Answer 3

good point. I cut this from the bigger .py, but left the import math behind. Just updated.

Answer 4

What was your intent with lines like this: print (multadd(6,3,3), 6*3+3)?

Answer 5

Just checking your function?

Answer 6

yah, the assignement says to do several tests of it.

Answer 7

1.
Write a function multadd that takes three parameters, a, b and c. Test your function well before moving on.

Answer 8

Well I would have expected a print similar to: print (multadd(6,3,3), "= 6*3+3")

Answer 9

That would have been a better way to do it eSpeX, definitely, though the intent was the same. I was just checking the function.

Answer 10

Looks pretty good to me.

Answer 11

If everything is working correctly, your output should look like:
sin(pi/4) + cos(pi/4)/2 is:
1.06066017178
ceiling(276/19) + 2 log_7(12) is:
17.5539788165
And for Yikes!
Try x=5 as a test; your answer should look like:
yikes(5) is 1.0303150673.

Did you get the expected returns?

Answer 12

>>>
21 =6*3+3
9 9
-9 -9
-39 -39
1.0606601717798212
17.55397881653925
yikes(5) = 1.0303150673048738
>>>

Answer 13

I did get the expected returns, so maybe there's nothing to be worried about (though, maybe there are some formatting issues with the output).

Answer 14

Really, my confusion, or concern was with the use of multadd:
e.g.
angle_test = multadd(1,math.sin(math.pi/4),math.cos(math.pi/4)/2)

There's nothing wrong with multiplying by 1 to get the answer, I just wondered if the problem had some other intent. We create a function to do a*b+c, it seemed like the answer would exploit each of those variables.

Could be overthinking it.

Answer 15

angle_test = multadd(math.cos(math.pi/4),1/2.0,math.sin(math.pi/4))

Answer 16

The intent was to get you building a compound argument using multiple functions.

Answer 17

Got it. Thanks for the feedback!

Answer 18

e., that's it! More complex, just like I wanted :)

Answer 19

You can do the same thing with:
ceiling_test = multadd(1,math.ceil(276/19.0),2*math.log(12,7))
ceiling_test = multadd(math.log(12,7),2,math.ceil(276/19.0))

Answer 20

Actually, less complex. I just used order of operations to do the addition on the left rather than the right. The multiplication will fire first no matter what. So rather than explicitly doing the multiplication in what I pass, I implicitly do it through the function by changing the order.