For f(x)=log(10x2−17x+7)(18x2−11x+1), we need:
Base >0: 10x2−17x+7>0⇒10(x−1)(x−7/10)>0⇒x<7/10 or x>1
Base =1: 10x2−17x+6=0⇒x=1/2 or x=6/5
Argument >0: 18x2−11x+1>0⇒18(x−1/2)(x−1/9)>0⇒x<1/9 or x>1/2
Intersecting conditions 1 and 3: (−∞,1/9)∪(1/2,7/10)∪(1,∞)
Removing base =1 points: x=1/2 is already excluded; x=6/5∈(1,∞) must be removed.
Domain: (−∞,1/9)∪(1/2,7/10)∪(1,∞)−{6/5}
So a=1/9,b=1/2,c=7/10,d=1,e=6/5.
90(a+b+c+d+e)=90(91+21+107+1+56)=10+45+63+90+108=316