(Ax + B) / (x^2 + a million) + (Cx + D) / (x^2 + 2) (Ax + B) * (x^2 + 2) + (Cx + D) * (x^2 + a million) = x^3 + x^2 + 2x + a million Ax^3 + Cx^3 + Bx^2 + Dx^2 + 2Ax + Cx + 2B + D = x^3 + x^2 + 2x + a million A + C = a million B + D = a million 2A + C = 2 2B + D = a million A + C = a million 2A + C = 2 2A + C - A - C = 2 - a million A = a million C = 0 2B + D - B - D = a million - a million B = 0 2B + D = a million D = a million (x + 0) * dx / (x^2 + a million) + (0x + a million) * dx / (x^2 + 2) x * dx / (x^2 + a million) + dx / (x^2 + 2) u = x^2 + a million du = 2x * dx x = sqrt(2) * tan(t) dx = sqrt(2) * sec(t)^2 * dt (a million/2) * du / u + sqrt(2) * sec(t)^2 * dt / (2 + 2 * tan(t)^2) => (a million/2) * du / u + (a million/sqrt(2)) * dt combine (a million/2) * ln|u| + (a million/sqrt(2)) * t + C => (a million/2)* ln|x^2 + a million| + (a million/sqrt(2)) * arctan(x / sqrt(2)) + C
Answers & Comments
Verified answer
1/x = 1/b - 1/a
1/x = (a - b)/(ab)
x = (ab)/(a - b)
Multiply to get rid of the fractions then solve for the variable:
1 / x + 1 / a = 1 / b
ab + bx = ax
ax - bx = ab
x(a - b) = ab
x = ab / (a - b)
Clearly the answer you have given is not correct, even if it was a typo.
(Ax + B) / (x^2 + a million) + (Cx + D) / (x^2 + 2) (Ax + B) * (x^2 + 2) + (Cx + D) * (x^2 + a million) = x^3 + x^2 + 2x + a million Ax^3 + Cx^3 + Bx^2 + Dx^2 + 2Ax + Cx + 2B + D = x^3 + x^2 + 2x + a million A + C = a million B + D = a million 2A + C = 2 2B + D = a million A + C = a million 2A + C = 2 2A + C - A - C = 2 - a million A = a million C = 0 2B + D - B - D = a million - a million B = 0 2B + D = a million D = a million (x + 0) * dx / (x^2 + a million) + (0x + a million) * dx / (x^2 + 2) x * dx / (x^2 + a million) + dx / (x^2 + 2) u = x^2 + a million du = 2x * dx x = sqrt(2) * tan(t) dx = sqrt(2) * sec(t)^2 * dt (a million/2) * du / u + sqrt(2) * sec(t)^2 * dt / (2 + 2 * tan(t)^2) => (a million/2) * du / u + (a million/sqrt(2)) * dt combine (a million/2) * ln|u| + (a million/sqrt(2)) * t + C => (a million/2)* ln|x^2 + a million| + (a million/sqrt(2)) * arctan(x / sqrt(2)) + C
1/x = 1/b - 1/a
1/x = ( a - b ) / (ab)
x = ab / ( a - b )
1/x + 1/a = 1/b
or, 1/x = 1/b - 1/a
or, 1/x = (a - b)/(ab)
or, x = (ab)/(a - b)..........[as a ≠ b, a - b ≠ 0]
Multiply the entire equation by xba to get rid of all fractions.
xba(1/x + 1/a) = xba(1/b)
So, we have ba + xb = xa
Place all terms concerning x onto one side to get
ba = xa -xb
Now factor out x on the right hand side.
ba = x(a - b)
Divide by (a - b) to isolate x.
x = ba / (a - b)
Hope this helps!
1/x = 1/b - 1/a
= (a-b)/ab
x = ab / (a-b)
your ans is right