Question

please dont use matlab to solve this problem!

thanks!

AT&T . 22! 12:29 * 19% Problem A (not from textbook): The drag (ir resistance experienced by airplanes can be simply modeledwing a cube equation in terms of velocity D(u) - +++ ayer where is the velocity of the plane (we will ignore units in this problem) and D is the Engineers working in a wind tunnelewa plane at different velocities and record the drag in the following table: 150 175 200 250 300 000 D742410758 167063099153915 127707 Calculate the last squares cubic equation D(v) for this data

Answer 1

%%Matlab code for cubic fit of given data clear all close all given data v=[150 175 200 250 300 400); D=[ 7424 10758 16706 30991 53915 127707 ); $Matrix form for cubic interpolation for i=1:length(v) A(1,1)=1; A(1,2)=v(i); A(1,3)=(V(i))*2; Ali,4)=(v(i))*3; end fprintf('A matrix is \n') disp (A) fprintf('D vector is \n') disp (D') fcoefficient matrix c=A\D'; fprintf('The coefficients are c=\n') disp(c) %plotting the data plot (v,D, 'r') DD=C(1)+c(2). *v+c(3).*v. *2+c(4). *v.^3; hold on plot (V,DD) title('Velocity vs. Drag plot') xlabel('velocity') ylabel('Drag') legend( 'Actual Data', 'Cubic Interpolation') 8888888888888888% End of Code 8%88888888888%% A matrix is 150 175 200 250 300 400 22500 30625 40000 62500 90000 160000 3375000 5359375 8000000 15625000 27000000 64000000 D vector is 7424 10758 16706 30991 53915 127707

The coefficients are c= 2037.992 20693037 -11.8745007145565 0.014331482578088 0.00200207505665177 Velocity vs. Drag plot Actuel Data Cubic Interpolafon Drag 150 8 250 300 350 velocity Published with MATLAB® R2018a

%%Matlab code for cubic fit of given data
clear all
close all

%given data
v=[150 175 200 250 300 400];
D=[7424 10758 16706 30991 53915 127707];

%Matrix form for cubic interpolation
for i=1:length(v)
    A(i,1)=1;
    A(i,2)=v(i);
    A(i,3)=(v(i))^2;
    A(i,4)=(v(i))^3;
end
fprintf('A matrix is \n')
disp(A)
fprintf('D vector is \n')
disp(D')

%coefficient matrix
c=A\D';
fprintf('The coefficients are c=\n')
disp(c)

%plotting the data
plot(v,D,'r*')
DD=c(1)+c(2).*v+c(3).*v.^2+c(4).*v.^3;
hold on
plot(v,DD)
title('Velocity vs. Drag plot')
xlabel('velocity')
ylabel('Drag')
legend('Actual Data','Cubic Interpolation')

%%%%%%%%%%%%%%%%% End of Code %%%%%%%%%%%%%%%