Given: f(x)=ex3−3x+1
⇒f′(x)=ex3−3x+1×(3x2−3)
⇒f′(x)=3×ex3−3x+1×(x−1)×(x+1)
So, for x∈(−∞,−1] f′(x)>0, hence f(x) is increasing function in given domain,
Now, finding a and b we get,
⇒a=x→−∞lim(ex3−3x+1)
⇒a=0
And b=f(−1)
⇒b=e−1+3+1
⇒b=e3
So, P(2b+4,a+2)
⇒P≡(2e3+4,2)

Now, finding the distance from the given line we get,
⇒d=1+e−6(2e3+4)+2e−3−4
⇒d=1+e−62(e3+e−3)
⇒d=e−311+e−62(1+e−6)
⇒d=e−321+e−6
⇒d=2e−61+1
⇒d=21+e6