Question

Find the value of ''a" so that 1-7x is a factor of -14x³-47x²-14x+a. Do it in Dickson method.

Answer 1

for 1-7x to be a factor
x=1/7 should satisfy the equation to be 0
so
-14(1/7)^3-47(1/7)^2-14(1/7)+a=0
(-14/343)-(47/49)-2+a=0
=> a=2/49+47/49+2
=>a=49/49+2
=>a=1+2=3
Answer a=3