Representa graficamente a função do segundo grau
A) f(x)=7x²-10x
-2
Soluções para a tarefa
Resposta:oi
Explicação passo-a-passo:
-x/f(x)=0
0=7x²-10x-2
7x²-10x-2=0
ax²+bxc=0
x=-b±√b²-4ac/2a
x=-(-10)±√(-10)²-4×7×(-2)/2×7
-
x=10±√(-10)²-4×7×(-2)/2×7
x=10±√100-4×7×(-2)/2×7
x=10±√100+56/2×7
x=10±√100+56/14
x=10±√156/14
x=10±2√39/14
+-
x=10+2√39/14
x=10-2√39/14
x=5+√39/7
x=10-2√39/14
x=5+√39/7
x=5-√39/7
2
x1=5-√39/7,x2=5+√39/7
x1≈-0,177857,x2≈1,60643
-y,x=0
f(0)=7×0²-10×0-2
0
f(0)=7×0-10×0-2
f(0)=7×0-0-2
f(0)=7×0-2
f(0)=0-2
f(0)-2
xER
f'(x)=d/dx(7x²-10x-2)
d/dx(f+g)=d/dx(f)+d/dx(g)
f'(x)=d/dx(7x²)+d/dx(-10x)-d/dx(2)
f'x=7×2x+d/dx(-10x)-d/dx(2)
f'(x)=7×2x-10-d/dx(2)
f'(x)=7×2x-10-0
f'(x)=14x-10
f(x)=7x²-10x-2,xER
f'(x)=14x-10
f'(x)=14x-10,xER
f'(x)=0
0=14x-10
x=5/7
(-∞,5/7),(5/7,+∞)
x1=0
x2=1
f'(0)=-10
x2=1
f'(0)=-10
f'(1)=4
x<5/7
5/7<x<+∞
x=5/7
f(x)=7x²-10x-2,x=5/7
x=5/7
f(5/7)-39/7
-39/7 em x=5/7
f(x)=7x²-10x-2
f(x)=7x²-10x-2,a=7,b=-10
>0
x
a b x=-b/2a
x=--10/2×7
x
x=5/7
f(x)=7x²-10x-2,x=5/7
f(5/7)=-39/7
-39/7 em x=5/7
lim (f(x)) e lim (f(x))
x→+∞
x→-∞
lim(7x²-10x-2)
x→+∞
lim(7x²-10x-2)
x→-∞
+∞
lim(7x²-10x-2)
x→-∞
+∞
+∞
lim(f(x)/x) e
x→+∞
lim(f(x)/x)
x→-∞
lim x→+∞(7x²-10x-2/x)
lim x→-∞(7x²-10x-2/x)
+∞
x→-∞(7x²-10x-2/x)
+∞
-∞
-∞
x-x
f(-x)=7×(-x)²-10x(-x)-2
f(-x)=7x²-10x(-x)-2
(-)×(-)=(+)
f(-x)=7x²+10x-2
f(-x)=f(x)
f(-x)=-f(x)