Gujarat BoardEnglish MediumSTD 12 ScienceMathsDifferentials, Errors and Approximations4 Marks
Question
Using differentials, find the approximate values of the following: $(15)^{\frac{1}{4}}$
✓
Answer
consider the function $\text{y}=\text{f}(\text{x})=\text{x}^{\frac{1}{4}}$ Let: x = 16 $\text{x}+\triangle\text{x}=15$ Then, $\triangle\text{x}=-1$ For x = 16 $\text{y}=(16)^{\frac{1}{4}}=2$ Let: $\text{dx}=\triangle\text{x}=-1$ Now, $\text{y}=(\text{x})^{\frac{1}{4}}$ $\Rightarrow\frac{\text{dy}}{\text{dx}}=\frac{1}{4(\text{x})^{\frac{3}{4}}}$ $\Rightarrow\Big(\frac{\text{dy}}{\text{dx}}\Big)_{\text{x}=16}=\frac{1}{32}$ $\therefore\triangle\text{y}=\text{dy}=\Big(\frac{\text{dy}}{\text{dx}}\Big)\text{dx}=\frac{1}{32}\times(-1)=\frac{-1}{32}$ $\Rightarrow\triangle\text{y}=\frac{-1}{32}=-0.03125$ $\therefore(15)^{\frac{1}{4}}=\text{y}+\triangle\text{y}=1.96875$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.