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If anyone could help me out with this - attached the sol bank answer below, the q is to find the exact value of f(x) using substitution and give the answer in form 2^q * p. I used the substitution u = sqrt(2-x) - attaching my working below too. Can someone show me where I've got wrong?

Last edited by velaris08; 1 month ago

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Did you changed the limits?

**mqb2766**)Did you changed the limits?

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If anyone could help me out with this - attached the sol bank answer below, the q is to find the exact value of f(x) using substitution and give the answer in form 2^q * p. I used the substitution u = sqrt(2-x) - attaching my working below too. Can someone show me where I've got wrong?

**velaris08**)If anyone could help me out with this - attached the sol bank answer below, the q is to find the exact value of f(x) using substitution and give the answer in form 2^q * p. I used the substitution u = sqrt(2-x) - attaching my working below too. Can someone show me where I've got wrong?

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#5

**velaris08**)

If anyone could help me out with this - attached the sol bank answer below, the q is to find the exact value of f(x) using substitution and give the answer in form 2^q * p. I used the substitution u = sqrt(2-x) - attaching my working below too. Can someone show me where I've got wrong?

(Original post by

thats because the limit does not exist

**MatureLikeManure**)thats because the limit does not exist

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(Original post by

Did you change the limits?

**mqb2766**)Did you change the limits?

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#7

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Don’t get why I’d need to? I know the answer does but I can’t lie, don’t get why they did…

**velaris08**)Don’t get why I’d need to? I know the answer does but I can’t lie, don’t get why they did…

If you notice, in the model solution the limits change from 0->2 to 2->0. This is because of the transformation

u = 2-x

The integration problem is now in terms of u, not x. See the pic at the top of

https://infinityisreallybig.com/2020...f-integration/

The integration (upper) limit is transformed.

Last edited by mqb2766; 4 weeks ago

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(Original post by

Youve transformed the integration variable from x to u. The original limits are in terms of x, you need to transform them as well to represent the corresponding values of u. It should be in your book?

If you notice, in the model solution the limits change from 0->2 to 2->0. This is because of the transformation

u = 2-x

The integration problem is now in terms of u, not x. See the pic at the top of

https://infinityisreallybig.com/2020...f-integration/

The integration (upper) limit is transformed.

**mqb2766**)Youve transformed the integration variable from x to u. The original limits are in terms of x, you need to transform them as well to represent the corresponding values of u. It should be in your book?

If you notice, in the model solution the limits change from 0->2 to 2->0. This is because of the transformation

u = 2-x

The integration problem is now in terms of u, not x. See the pic at the top of

https://infinityisreallybig.com/2020...f-integration/

The integration (upper) limit is transformed.

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