Question

Se considera functia f:R→R, f(x) = ax+b. Determinati a si b stiind ca punctele A(1,1) si B(2,0) apartin graficului functiei.

Answer 1

f:R-->R, f(x)=ax+b

A(1;1)€Gf=>f(1)=1

a×1+b=1

B(2;0)=>f(2)=0

a×2+b=0

a+b=1=>a=1-b

2(1-b)+b=0

2-2b+b=0/-2

-b= -2 => b=2

a+2=1 /-2

a= -1