1ans is -16
if 1/x3(x+2) = A/x+B/x2+C/x3+D/(x+2) then value of |1/A 1/B |
|1/D 1/C |
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7 Answers
62if 1/x3(x+2) = A/x+B/x2+C/x3+D/(x+2) then value of |1/A 1/B |
|1/D 1/C |
multiply both sides by (x+2)
1/x3 = (x+2)(A/x+B/x2+C/x3)+D
substitute x=-1
-1/8=D
also, multiply both sides by x3
1/(x+2) = Ax2+Bx+C+Dx3/(x+2)
substitute x=0
we get 1/2=C
62for the other parts, balance the pwers of x by multiplying by x3.(x+2)
1isn't it easy if we write like this 1=A(x3+2x2)+B(x2+2x)+C(x+2)+Dx3
=> A+D=0
2A+B=0
2B+C=0
and 2C=1
solving these u cld get the values
62yes indeed honey it makes it much easier...
I forgot that method.. :)
Good that you recalled this one :)
