5.2-bo'lim : Noaniq integrallarni hisoblash
9. \( \displaystyle \int{{\frac{7}{{3{y^6}}} + \frac{1}{{{y^{10}}}} - \frac{2}{{\sqrt[3]{{{y^4}}}}}\,dy}}\) ni baholang.
Yechim
Biz birinchi navbatda ildizni kasr ko'rsatkichiga aylantirishimiz va maxrajdagi \(y\) ni manfiy darajali suratga o'tkazishimiz kerak.
\[\int{{\frac{7}{{3{y^6}}} + \frac{1}{{{y^{10}}}} - \frac{2}{{\sqrt[3]{{{y^4}}}}}\,dy}} = \int{{\frac{7}{{3{y^6}}} + \frac{1}{{{y^{10}}}} - \frac{2}{{{y^{\frac{4}{3}}}}}\,dy}} = \int{{\frac{7}{3}{y^{ - 6}} + {y^{ - 10}} - 2{y^{ - \frac{4}{3}}}\,dy}}\]Esda tutingki, birinchi hadning maxrajidagi “3” maxrajda qoladi va \(y\) bilan yuqoriga siljimaydi.
2-qadam
Ildizni kasr ko‘rsatkichiga aylantirganimizdan va \(y\) maxrajdan chiqqanimizdan so‘ng, integralni baholashdan boshqa ishimiz qolmaydi.
\[\begin{align*}\int{{\frac{7}{{3{y^6}}} + \frac{1}{{{y^{10}}}} - \frac{2}{{\sqrt[3]{{{y^4}}}}}\,dy}} & = \int{{\frac{7}{3}{y^{ - 6}} + {y^{ - 10}} - 2{y^{ - \,\frac{4}{3}}}\,dy}}\\ & = \frac{7}{3}\left( {\frac{1}{{ - 5}}} \right){y^{ - 5}} + \left( {\frac{1}{{ - 9}}} \right){y^{ - 9}} - 2\left( { - \frac{3}{1}} \right){y^{ - \,\frac{1}{3}}} + c\\ & = \require{bbox} \bbox[2pt,border:1px solid black]{{ - \frac{7}{{15}}{y^{ - 5}} - \frac{1}{9}{y^{ - 9}} + 6{y^{ - \,\frac{1}{3}}} + c}}\end{align*}\]“+c” ni qo‘shishni unutmang, chunki biz integralni olish uchun qaysi funktsiyani farqlaganimizni so‘raayotganimizni bilamiz va doimiyning hosilasi nolga teng va shuning uchun javobga buni qo‘shishimiz kerak.