Given :
Find f(7.5) using Newton's Backward difference formula.
Newton's Backward Difference Formula, we can work with the given data and the differences between successive values. The formula for Newton's Backward Difference is:
f(x)=f(x0)+(x−x0)Δf(x0)+(x−x0)(x−x1)Δ2f(x0,x1)+…
Given data:
f(x):1128314415546576819
First, we need to construct a backward difference table. The differences can be calculated as follows:
Now, we can use the backward difference formula:
f(7.5)=f(7)+(7.5−7)Δf(7)+(7.5−7)(7.5−6)Δ2f(7)+(7.5−7)(7.5−6)(7.5−5)Δ3f(7)+(7.5−7)(7.5−6)(7.5−5)(7.5−4)Δ4f(7)+(7.5−7)(7.5−6)(7.5−5)(7.5−4)(7.5−3)Δ5f(7)
Now, substitute the values from the backward difference table: f(7.5)=6+0.5(4)+0.5(0.5)(13)+0.5(0.5)(0.5)(4)+0.5(0.5)(0.5)(0.5)(7)
Now, calculate the values:
f(7.5)=6+2+1.625+0.5+0.4375
f(7.5)=10.5625
So, f(7.5)≈10.5625.