Why is naive Bayes so ‘naive’ ?

Because it assumes that all of the features in a data set are equally important and independent. But in real world scenarios these assumption are rarely true. Also it has no regularization term so it is prone to overfitting

Find derivative of $$ x^{2} $$

Using power rule : $$ \frac{d}{dx}(x^{n})=nx^{n-1} $$ Solution: $$ 2x$$

Simplify the expression: $$ 2(a -3) + 4b - 2(a -b -3) + 5 $$

First Step: Open brackets and apply multiplication operation $$ 2a - 6 + 4b - 2a +2b +6 +5$$ Second Step: Combine $$ a $$ variable and $$ b $$ variable and other constants as: $$ 2a - 2a + 4b +2b - 6 + 6$$ Third Step: Simplify as: $$ 6b $$ and this is the required answer