Heavy reward, help with the matlab problem, thank you 50

Hello landlord.

The procedure is as follows: t=linspace(0,2*pi,50); % is evenly taken by 50 points in the interval [0:2].

y1=sin(2*; y2=3*cos(t+;%y1=sin(2*; y2=3cos(t+;

I hope it will be helpful to the landlord, and I hope the landlord will adopt it, and welcome to communicate.

Question 2 is a drawing problem, which can be implemented in the following way.

1. Determine the range of x, that is, create a vector group of x.

x=0:pi/10:4*pi

2. Chi Xiao calculates the values of y and z respectively, ie.

y=sin(x)+cos(x)

z=sin(x)-cos(x)

3. Use the plot function to plot the curves of y(x) and z(x) respectively, i.e.

plot(x,y,'k--p',x,z,'k--p'4. Use the xlim and ylim functions to determine the range of the x-axis and y-axis.

xlim([0,15])

ylim([,5、Use the grid on command to draw a coordinate grid.

6. Use the xlabel and ylabel functions to label the code with the names of the x-axis and y-axis.

xlabel('x');ylabel('y');

7. Use the text function to annotate the function expression.

8. Realization.

x=0:pi/10:4*pi;

y=sin(x)+cos(x);

z=sin(x)-cos(x);

plot(x,y,'k--p',x,z,'r--p');

xlim([0,15])

ylim([,grid on

xlabel('x');ylabel('y');

text(2,,'y=sin(x)+cos(x)')text(,,'z=sin(x)-cos(x)'Run the results. <>

Question 1 is a matrix problem, which cannot be seen clearly because the problem is omitted.

According to the relationship between the current i and the time t provided by the subject, the relationship between the voltage drop and the time is determined. Its solution idea:

1. Use the diff difference (derivative) function to find the DI DT2, according to Faraday's law of electromagnetic induction: VL=L*Di DT, find the VL value 3, use the interpolation function of INTERP1 to find the corresponding VL value when T=0::, in order to fit the accurate function.

4. If you don't know the specific function model, you generally use higher-order polynomial functions to approximate it. Using the polyfit fitting function, the coefficients of the polynomial are found to obtain the polynomial function vl(t).

5. Use the polyval function to find the value of the polynomial 6. Use the plot function to plot the function relationship between the voltage drop vl and the time t.