Express (16x+78)/(2x^2+25x+63) as two fractions

Firstly factorise the denominator to get (2x+7)(x+9). Then make the fraction equal to the seperate fractions with constants.

E.g 16x+78/2x^2+25x+63=A/(2x+7)+B/(x+9). then multiply accross by the denominator to get 16x+78=A(x+9)+B(2x+7)

the subtitute in x to make one term equal 0. e.g x=-9.to get -66=-11B therefor B=-6. then substitue in x=-7/2 to get 22=(11/2)B therfore B=4

so the answer is 4/(2x+7)+6/(x+9)

GD

Related Maths A Level answers

All answers ▸

Find the volume of revolution when the area B is rotated 2 pi radians about the x axis


Chris claims that, “for any given value of x , the gradient of the curve y=2x^3 +6x^2 - 12x +3 is always greater than the gradient of the curve y=1+60x−6x^2” . Show that Chris is wrong by finding all the values of x for which his claim is not true.


How to integrate and differentiate ((3/x^2)+4x^5+3)


Differentiate the function f(x) = 2x^3 + (cos(x))^2 + e^x