If f(x)=1+3xlog3 and F(x) be its antiderivative which assume the value 7 for x = 2. The value of x for which the curve F(x) cuts the abscissa axis is
0
1
2
3
F(x)=∫f(x)dx+C=x+3x+C but F(2)=7 so 7=2+9+C
⇒C=−4. Hence F(x)=x+3x−4 Now F(x)=0
⇒x=1