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LBK
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Hello, I am having a hard time getting my errors to come out to what the book says the answers should be. My approximations are correct, so I think I'm just misunderstanding how to find K.
Q.a) Find the approximations T8 and M8 for ∫(0 to 1) cos(x2)dx
I found these to be T8=0.902333 and M8=0.905620
b) Estimate the errors in the approximations. And here's where my numbers don't match. What I did:
2nd deriv f''(x)=-2x*sin(x2)-4x2cos(x2)
since the graph is bounded by |1| I thought the max. would be at f''(0) but that would make f''(0)=0
So I'm really confused on where to go from here.
FYI--the book answer gives a value of ET=<or=0.0078 and EM=<or=0.0039
I have the formula for error for trapezoidal as <or= [K(b-a)3] / 12n2
In this case then, I should have (b-a)3=1 and 12n3=768
Working backward from the book's correct answer that would make 0.0078=K/768 and K=5.99
So I'm not seeing where that would come from. Any help, please? I'm really struggling in this class and very confused.
Q.a) Find the approximations T8 and M8 for ∫(0 to 1) cos(x2)dx
I found these to be T8=0.902333 and M8=0.905620
b) Estimate the errors in the approximations. And here's where my numbers don't match. What I did:
2nd deriv f''(x)=-2x*sin(x2)-4x2cos(x2)
since the graph is bounded by |1| I thought the max. would be at f''(0) but that would make f''(0)=0
So I'm really confused on where to go from here.
FYI--the book answer gives a value of ET=<or=0.0078 and EM=<or=0.0039
I have the formula for error for trapezoidal as <or= [K(b-a)3] / 12n2
In this case then, I should have (b-a)3=1 and 12n3=768
Working backward from the book's correct answer that would make 0.0078=K/768 and K=5.99
So I'm not seeing where that would come from. Any help, please? I'm really struggling in this class and very confused.
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