Question

radical din 2x-1-x=-8

Answer 1

√2x-1-x=-8
√2x=-8+1+x
√2x=-7+x
2x=x²-14x+49
2x-x²+14x-49=0
16x=x²-49=0
-x²+16x-49=0
x²-16x+49=0
x=-(-16)+-√(-16)²-4*1*49/2*1
x=16+-√256-196/2
x=16+-√60/2
x=16+-2√15/2


x=16+2√15/2
x=16-2√15/2

x=8+√15
x=8-√15

√2(8+√15)-1-(8+√15)=-8
si acum invers
√2(8-√15)-1-(8-√15)=-8

-8=-8
-2,25403=-8

adica
x=8+√15
x≠8-√15


deci in final x=8+√15