Question

determine a raiz da função?

Answer 1

-x²+8x-1=0
∆=b²-4ac
∆=8²-4.(-1).(-1)
∆=64-4
∆=60

x=-b±√∆
————
2a

x=-8±√60
————
2.(-1)

x=-8±2√15
—————
-2

x¹=-8+2√15 -6√15
-------------- = ----------- = 3√15
-2 -2

x²=-8-2√15 -10√15
------------ = ------------- = 5√15
-2 -2