Recent content by rojak44

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    Engineering Discover the Basics of Pneumatic Circuits: Tips for Success | TQ

    i have done them all once but most of them unsuccessfully,due to no basic,guidance,lack of time and it is my first time seeing it. im now trying to figure what happen if all of them are successful connected. i have been searching through the net for hours but failed to find information on them...
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    Understanding Quality: Uncovering the Relationship between Variables

    thanks! i understand now.. s1=s2.. im using s to find the quality x=(s-sf)/sfg i got the answer now,thank you very much!
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    Understanding Quality: Uncovering the Relationship between Variables

    thank for the reply ^ ^ my english is not so good,here what i understand. find the quality x=(v-vf)/vfg, then substitute it in u=uf+xufg. im confuse now.. i only have mass of 1.5kg,how do i find the specific volume? v=V/m V=?
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    Understanding Quality: Uncovering the Relationship between Variables

    sorry if i posted this in wrong section.. im having problem on where the value in the circle come from,can someone give me an answer or a hint. TQ
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    Solve Integral of t/1+t^2 - 1/2 ln (1+t^2) + c

    just assume it as dy/dt sorry I am not good in english. im using quotient rule to solve that.
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    Solve Integral of t/1+t^2 - 1/2 ln (1+t^2) + c

    here is my answer,do tell whether it is right or wrong. 2e^mt(m cos 2m+cos 2m+2m sin 2m)/(cos 2m)^2
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    Solve Integral of t/1+t^2 - 1/2 ln (1+t^2) + c

    it is correct except the cos have no bracket, cos2m i have no idea,im having trouble to decide whether it is dy/dm or dy/dt
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    Solve Integral of t/1+t^2 - 1/2 ln (1+t^2) + c

    thank you! :) i got one more question, differentiate y= 2m e^mt/cos 2m is it dy/dt or dy/dm? 2m e^mt, e^mt if differentiate = e^mt or me^mt?
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    Solve Integral of t/1+t^2 - 1/2 ln (1+t^2) + c

    u mean remove the t? so it will become 1/2u? here, = int 1/2u du = int u^-1/2 du = 1/2 int u^-1 du =1/2 [ln u]+c = 1/2 ln (1+t^2)+c (answer) am i correct? btw if we remove t,it will become 1/2u right since it was 1t/2tu?
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    Solve Integral of t/1+t^2 - 1/2 ln (1+t^2) + c

    could anyone help me here? pls..
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    Solve Integral of t/1+t^2 - 1/2 ln (1+t^2) + c

    here it is,pls correct me if I am wrong. int t/1+t^2 dt u = 1+t^2 du/dt = 2t dt = 1/2t du = int (t/u)(1/2t du) = int t/2tu du = 1/2 int t/tu du = 1/2 int t(tu)^-1 du = 1/2 int t^0 u^-1 du = 1/2 [t^1 ln u]+c = 1/2 ln t (1+t^2)+c (answer)
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    Solve Integral of t/1+t^2 - 1/2 ln (1+t^2) + c

    im using the integration using substitution.. im confuse right now.. can anyone give me the full calculation or what method i should use.
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    Solve Integral of t/1+t^2 - 1/2 ln (1+t^2) + c

    hello there,im having trouble with this question.. find int t/1+t^2 dt my answer is 1/2 ln t (1+t^2)+c but the answer that i have copy is 1/2 ln (1+t^2)+c maybe i have copy it wrongly,can someone tell me which one is right? thx.. :smile: