Question

Se considera functia f:r ->r , f(x)= -2x+7. sa se determine a e R astfel incat a la a2 a - 2a - f(3) =14

Answer 1

[tex]f:\mathbb{R}\rightarrow \mathbb{R},f(x)=-2x+7\\ a^2-2a-f(3)=14\\ a^2-2a-1=14\\ a^2-2a-15=0\\ \Delta=4+4\cdot 15=64\Rightarrow \sqrt{\Delta}=8\\ a_1=\dfrac{2+8}{2}=5\\ a_2=\dfrac{2-8}{2}=-3\\ S=\{5,-3\}[/tex]