Question

differentiate up to four times bln|y|

Answer 1

Differentiate up to four times $bln|y|$

Solution: $f(y) = bln|y|$

$$\frac{df}{dy} = \frac{b}{y}$$ $$\frac{d^2f}{dy^2} = -\frac{b}{y^2}$$ $$\frac{d^3f}{dy^3} = \frac{2b}{y^3}$$ $$\frac{d^4f}{dy^4} = -\frac{6b}{y^4}$$

Answer: $\frac{d^4f}{dy^4} = -\frac{6b}{y^4}$