[tex]f(x)=-2x+\frac{3}{2}[/tex]
∩OX, y=0
[tex]-2x+\frac{3}{2}=0\\\\2x=\frac{3}{2} \\\\x=\frac{3}{4}\\\\A(\frac{3}{4},0)[/tex]
∩OY, x=0
[tex]y=\frac{3}{2}\\\\B(0,\frac{3}{2})[/tex]
Le reprezinti pe axa xOy
[tex]f(3a+4)=a+\frac{1}{2}\\\\-2(3a+4)+\frac{3}{2}=a+\frac{1}{2}\\\\-12a-16+3=2a+1\\\\14a=-14\\\\a=-1[/tex]
[tex]S=f(1)+f(2)+...+f(50)\\\\S=-2\times 1+\frac{3}{2}-2\times 2+\frac{3}{2}-..-2\times 50+\frac{3}{2}[/tex]
[tex]\frac{3}{2}[/tex] apare de 50 de ori
Dam factor comun -2
[tex]S=-2(1+2+3+...+50)+\frac{3}{2}\times 50\\\\S=-50\times 51+75\\\\S=-2475[/tex]
