`(x^2+5)/((x+1)(x^2-2x+3))`
Let`(x^2+5)/((x+1)(x^2-2x+3))=A/(x+1)+(Bx+C)/(x^2-2x+3)`
`(x^2+5)/((x+1)(x^2-2x+3))=(A(x^2-2x+3)+(Bx+C)(x+1))/((x+1)(x^2-2x+3))`
`(x^2+5)/((x+1)(x^2-2x+3))=(Ax^2-2Ax+3A+Bx^2+Bx+Cx+C)/((x+1)(x^2-2x+3))`
`:.(x^2+5)=Ax^2-2Ax+3A+Bx^2+Bx+Cx+C`
`x^2+5=(A+B)x^2+(-2A+B+C)x+3A+C`
equating the coefficients of the like terms,
`A+B=1`
`-2A+B+C=0`
`3A+C=5`
Now let's solve the above three equations to find the values of A,B and C,
Express C in terms of A from the third equation,
`C=5-3A`
Substitute the above expression of C in second equation,
`-2A+B+5-3A=0`
`-5A+B+5=0`
`-5A+B=-5`
Now subtract the first equation from the above equation,
`(-5A+B)-(A+B)=-5-1`
`-6A=-6`
`A=1`
Plug the value of A in the first and...
`(x^2+5)/((x+1)(x^2-2x+3))`
Let`(x^2+5)/((x+1)(x^2-2x+3))=A/(x+1)+(Bx+C)/(x^2-2x+3)`
`(x^2+5)/((x+1)(x^2-2x+3))=(A(x^2-2x+3)+(Bx+C)(x+1))/((x+1)(x^2-2x+3))`
`(x^2+5)/((x+1)(x^2-2x+3))=(Ax^2-2Ax+3A+Bx^2+Bx+Cx+C)/((x+1)(x^2-2x+3))`
`:.(x^2+5)=Ax^2-2Ax+3A+Bx^2+Bx+Cx+C`
`x^2+5=(A+B)x^2+(-2A+B+C)x+3A+C`
equating the coefficients of the like terms,
`A+B=1`
`-2A+B+C=0`
`3A+C=5`
Now let's solve the above three equations to find the values of A,B and C,
Express C in terms of A from the third equation,
`C=5-3A`
Substitute the above expression of C in second equation,
`-2A+B+5-3A=0`
`-5A+B+5=0`
`-5A+B=-5`
Now subtract the first equation from the above equation,
`(-5A+B)-(A+B)=-5-1`
`-6A=-6`
`A=1`
Plug the value of A in the first and third equation to get the values of B and C,
`1+B=1`
`B=1-1`
`B=0`
`3(1)+C=5`
`C=5-3`
`C=2`
`:.(x^2+5)/((x+1)(x^2-2x+3))=1/(x+1)+2/(x^2-2x+3)`
Now let's check it algebraically,
`1/(x+1)+2/(x^2-2x+3)=(1(x^2-2x+3)+2(x+1))/((x+1)(x^2-2x+3))`
`=(x^2-2x+3+2x+2)/((x+1)(x^2-2x+3))`
`=(x^2+5)/((x+1)(x^2-2x+3))`
Hence it is verified.
No comments:
Post a Comment