Respuesta :

30.

[tex]g(x)=2x^2+18x-14\\\\a)\\g(9)=2\cdot9^2+18\cdot9-14=162+162-14=310\\\\b)\\ g(3x)=2(3x)^2+18(3x)-14=18x^2+54x-14\\\\c)\\ g(1+5m)=2(1+5m)^2+18(1+5m)-14=\\\\=2(1+10m+25m^2)+18+90m-14=2+20m+50m^2+4+90m=\\\\=50m^2+110m+6[/tex]

31.

[tex]h(y)=-3y^3-6y+9\\\\a)\\h(4)=-3(4)^3-6(4)+9=-3\cdot64-24+9=-192-15=-207\\\\ b)\\h(-2y)=-3(-2y)^3-6(-2y)+9=24y^3+12y+9\\\\c)\\h(5b+3)=-3(5b+3)^3-6(5b+3)+9=\\\\=-3[(5b)^3+3\cdot(5b)^2\cdot3+3\cdot5b\cdot3^2+3^3)-30b-18+9=\\\\=-375b^3-675b^2-405b-81-30b-9=-375b^3-675b^2-435b-90[/tex]

32.

[tex]f(t)=\dfrac{4t+11}{3t^2+5t+1}\\\\a)\\f(-6)=\dfrac{4(-6)+11}{3(-6)^2+5(-6)+1}=\dfrac{-24+11}{3(36)-30+1}=\dfrac{-13}{108-29}=-\dfrac{13}{79}\\\\b)\\f(4t)=\dfrac{4(4t)+11}{3(4t)^2+5(4t)+1}=\dfrac{16t+11}{48t^2+20t+1}\\\\c)\\f(3-2a)=\dfrac{4(3-2a)+11}{3(3-2a)^2+5(3-2a)+1}=\dfrac{12-8a+11}{3(9-12a+4a^2)+15-10a+1}=\\\\=\dfrac{-8a+23}{27-36a+12a^2+16-10a}=\dfrac{-8a+23}{12a^2-46a+43}[/tex]

33.

[tex]g(x)=\dfrac{3x^3}{x^2+x-4}\\\\a)\\g(-2)=\dfrac{3(-2)^3}{(-2)^2+(-2)-4}=\dfrac{3(-8)}{4-2-4}=\dfrac{-24}{-2}=12\\\\b)\\g(5x)=\dfrac{3(5x)^3}{(5x)^2+(5x)-4}=\dfrac{3(125x^3)}{25x^2+5x-4}=\dfrac{375x^3}{25x^2+5x-4}\\\\c)\\g(8-4b)=\dfrac{3(8-4b)^3}{(8-4b)^2+(8-4b)-4}=\dfrac{3[8^3-3\cdot8^2\cdot4b+3\cdot8\cdot(4b)^2-(4b)^3]}{64-64b+16b^2+8-4b-4}=\\\\=\dfrac{3(512-768b+384b^2-64b^3)}{16b^2-68b+68}=\dfrac{3\cdot4(128-192b+96b^2-16b^3)}{4(4b^2-17b+17)}=\\\\=\dfrac{384-576b+288b^2-48b^3}{4b^2-17b+17}[/tex]