[填空题]
Consider the differentl*9 j ic+.7n3k2auir 2m jizzer8h6aoial equation .*twj2fexykj6y;f;r zcs6+j86atd p$\frac{\mathrm{d} y}{\mathrm{~d} x}-\frac{y}{x}=\frac{1}{2}$ , where x>0 .
1. Given that y(1)=2 , use Euler's method with step length h=0.5 to find an approximation for y(3) . Give your answer correct to two significant figures.≈
2. Solve the equation $ \frac{\mathrm{d} y}{\mathrm{~d} x}-\frac{y}{x}=\frac{1}{2}$ for y(1)=2 .
3. Find the percentage error when y(3) is approximated by the final rounded value found in part (a). Give your answer correct to two significant figures.≈ %