rejected by B4B.

checked author's solution. it will return 4. not an issue.

Great kata, quite simple to be honest yet nice, keep it going.

plotting f'(x) on a graph, then finding the y value at a point x, is what the description is saying.

All languages obey this rule as of now, closing

OP solved it, closing

Approved

python new test framework is required. updated in this fork

That test doesn't exist in either the sample or full test suites. There is a similar one -5x^2+10x+4, for which the gradient is indeed -20; I think you've modified the tests and are now failing them because you modified them. Probably not a kata issue.

is it just me or are some of the python tests just wrong?

this test (test.assert_equals(differentiate("-x^2+10x+4", 3), -20)) says that the slope of -x^2+10x+4 at point 3 is 20 when in reality it should be 4.

I calculated this myself and also let wolfram alpha do it: https://www.wolframalpha.com/input?i=derivative+of+-x%5E2%2B10x%2B4+at+3

I passed most tests, but a big part of them is still completely wrong. Am i not getting something here?

best!

✨

This kata is a subject to deduplication process here: https://github.com/codewars/content-issues/issues/203.
Please join the discussion to help us identify duplicate kata and retire them.

Really enjoyed the kata.

Used regex but didn't have full understanding of some functions and the syntax of regex but managed it nonetheless after spending some time printing the output of my regex splits.
Really brute forced this one and when I saw other solutions after solving, I realised how much I need to learn new libraries.

But thanks for the kata, it taught me a few new tricks.