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Raskite apibreztinius integralus


1)

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2)

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Labai didelis ačiū už suteiktą pagalbą.

nejaugi nieks nepagelbes? :(

1. [tex]\int_{0}^{4}\frac{1}{\sqrt{x}-3} dx[/tex]

Isivedam keitinius: [tex]t=\sqrt{x}[/tex];  [tex]dt=\frac{1}{2\sqrt{x}}dx\Rightarrow 2tdt=dx[/tex]

[tex]\int_{0}^{4}\frac{2t}{t-3}dt=\int_{0}^{4}2+\frac{6}{t-3}dt= 2t+6ln|t-3||_{0}^{4}=2\sqrt{x}+6ln|\sqrt{x}-3||_{0}^{4}=4+6ln|-1|-6ln|-3|=4-ln(729)[/tex]

2.

[tex]\int_{-4}^{1}\frac{x}{\sqrt{(5-x)^3}}dx[/tex]

Isivedam keitinius: [tex]t=5-x[/tex];  [tex]x=5-t[/tex];  [tex]dt=-dx\Rightarrow -dt=dx[/tex]

[tex]-\int_{-4}^{1}\frac{5-t}{t^{\frac{3}{2}}}dt=-\int_{-4}^{1}\frac{5}{t^{\frac{3}{2}}}dt+\int_{-4}^{1}\frac{t}{t^{\frac{3}{2}}}dt=\frac{10}{\sqrt{t}}+2\sqrt{t}|_{-4}^{1}[/tex][tex]=\frac{10}{\sqrt{5-x}}+2\sqrt{5-x}|_{-4}^{1}=(5+4)-(\frac{10}{3}+6)=-\frac{1}{3}[/tex]

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