We have to find integration of f(x) having upper limit 1.05 and lower limit 1
[tex]\\ \rm\longmapsto \displaystyle{\int^{1.05}_1}x^3dx[/tex]
[tex]\\ \rm\longmapsto \left[\dfrac{3x^{3+1}}{3+1}\right]^{1.05}_1[/tex]
[tex]\\ \rm\longmapsto \left[\dfrac{3x^4}{4}\right]^{1.05}_1[/tex]
[tex]\\ \rm\longmapsto \dfrac{3(1.05)^4-3(1)^4}{4}[/tex]
[tex]\\ \rm\longmapsto \dfrac{3(1.2)-3(1)}{4}[/tex]
[tex]\\ \rm\longmapsto \dfrac{3.6-3}{4}[/tex]
[tex]\\ \rm\longmapsto \dfrac{0.6}{4}[/tex]
[tex]\\ \rm\longmapsto 2.4[/tex]