Question

f:R->R
f(x)=4x-5
Precizati care din punctele de mai jos apartin Gf :
a) A(1;1)
b)B(2;3)
c) C(0;5)
d)D( 1/4; -4).

Answer 1

a. A (1,1) adica f(1)=1 => 4-5 = -1  (F)
b. B (2,3) adica f(2)=3 => 8-5 = 3   (A)
c. C (0,5) adica f(0)=5 => 0-5 = -5 (F)
d. D (1/4, -4) adica f(1/4) = -4 => 1-5=-4 (A)

Punctele B si D apartin Gf