第一问:可以用dsolve()求得其特解,
>> syms y(x)
>> D2y=diff(y,2);Dy=diff(y,1);
>> y=dsolve(D2y-2*Dy+4*y==x,y(0)==0,Dy(0)==1)
运行结果,
y=x/4 - (exp(x)*cos(3^(1/2)*x))/8 + (7*3^(1/2)*exp(x)*sin(3^(1/2)*x))/24 + 1/8
第二问:∫f(x)的定积分值
>>I=quad(@(x)eval(y),0,1,1e-12)
运行结果,I = 0.80274
第三问:可以用fplot()绘出f(x)的图像
>>fplot(@(x)eval(y),[-1,1])
运行结果,