given that f(x) = x^4 - 27x^2 - 14x + 120 can be expressed as ( x^2 + a )^2 - ( bx + 7 )^2 where a,b are constant. find the values of a and b. hence, or otherwise, factorise f(x) completely. the value of a and b are -13 and 1 respectively. so, f(x) = ( x^2 - 13 )^2 - ( x + 7 )^2 one way to factorise f(x) completely is to substitute value of x so that we can get f(x) = 0. is there any other easier way since there is a keyword "HENCE" in the question. thank you.