Question

1)  x⁴-1 supra x²+1 prin x²+1.
2) Scrieti sub forma de interval multimea solutiilor reale ale inecuatiei 4x-3≤2x+15.
3) In paralelipipedul ABCD A`B`C`D` ,AB=4 cm ,BC=5 cm AA`=6 cm.Determinati lungimea segmentului BD`
4) Calculati volumul unui cilindru circular drept cu raza bazei de 4 cm si generatoarea de 2 cm .

Answer 1

1) ⇒(x²-1)(x²+1)/(x²+1) se simplifica=x²-1
x²-1=0
x²=1
X1=1
X2=-1
S={-1,1}
2)4x-3≤2x+15
4x-2x≤15+3
2x≤18
x≤18/2
x≤9
x∈(-α,9]

Answer 2

2) 4x-2x≤18 => x≤9 x e (-infinit ; 9]
3) BD'=d => d²=L²+l²+h² => d²=16+25+36=> d²=77 => d=√77
4) V= πR²h=> V=π 16 x 2=> V=32π