Question and Answers Forum

All Questions      Topic List

None Questions

Previous in All Question      Next in All Question      

Previous in None      Next in None      

Question Number 117143 by aurpeyz last updated on 09/Oct/20

Answered by prakash jain last updated on 13/Oct/20

((2x^4 −2x^3 +4x^2 −2x)/((x−1)(x^2 +1)))  =Ax+B+(C/(x−1))+((Dx+E)/(x^2 +1))  2x^4 −2x^3 +4x^2 −2x=    (Ax+B)(x−1)(x^2 +1)+C(x^2 +1)+(Dx+E)(x−1)  coefficient of x^4   ⇒A=2  put x=0 ⇒−B+C−E=0     put x=1⇒2C=2⇒C=1  put x=i⇒2+2i−4−2i=(Di+E)(i−1)       −2=−(E+D)+i(E−D)        ⇒E=D=1  −B+C−E=0⇒B=0  A=2,B=0,C=1,D=1,E=1  2x+(2/(x−1))+((x+1)/(x^2 +1))

$$\frac{\mathrm{2}{x}^{\mathrm{4}} −\mathrm{2}{x}^{\mathrm{3}} +\mathrm{4}{x}^{\mathrm{2}} −\mathrm{2}{x}}{\left({x}−\mathrm{1}\right)\left({x}^{\mathrm{2}} +\mathrm{1}\right)} \\ $$$$={Ax}+{B}+\frac{{C}}{{x}−\mathrm{1}}+\frac{{Dx}+{E}}{{x}^{\mathrm{2}} +\mathrm{1}} \\ $$$$\mathrm{2}{x}^{\mathrm{4}} −\mathrm{2}{x}^{\mathrm{3}} +\mathrm{4}{x}^{\mathrm{2}} −\mathrm{2}{x}= \\ $$$$\:\:\left({Ax}+{B}\right)\left({x}−\mathrm{1}\right)\left({x}^{\mathrm{2}} +\mathrm{1}\right)+{C}\left({x}^{\mathrm{2}} +\mathrm{1}\right)+\left({Dx}+{E}\right)\left({x}−\mathrm{1}\right) \\ $$$${coefficient}\:{of}\:{x}^{\mathrm{4}} \:\:\Rightarrow{A}=\mathrm{2} \\ $$$${put}\:{x}=\mathrm{0}\:\Rightarrow−{B}+{C}−{E}=\mathrm{0}\:\:\: \\ $$$${put}\:{x}=\mathrm{1}\Rightarrow\mathrm{2}{C}=\mathrm{2}\Rightarrow{C}=\mathrm{1} \\ $$$${put}\:{x}={i}\Rightarrow\mathrm{2}+\mathrm{2}{i}−\mathrm{4}−\mathrm{2}{i}=\left({Di}+{E}\right)\left({i}−\mathrm{1}\right) \\ $$$$\:\:\:\:\:−\mathrm{2}=−\left({E}+{D}\right)+{i}\left({E}−{D}\right) \\ $$$$\:\:\:\:\:\:\Rightarrow{E}={D}=\mathrm{1} \\ $$$$−{B}+{C}−{E}=\mathrm{0}\Rightarrow{B}=\mathrm{0} \\ $$$${A}=\mathrm{2},{B}=\mathrm{0},{C}=\mathrm{1},{D}=\mathrm{1},{E}=\mathrm{1} \\ $$$$\mathrm{2}{x}+\frac{\mathrm{2}}{{x}−\mathrm{1}}+\frac{{x}+\mathrm{1}}{{x}^{\mathrm{2}} +\mathrm{1}} \\ $$

Terms of Service

Privacy Policy

Contact: info@tinkutara.com