1.
8^(2x+3)+8^(2x+1)-8^2x=519*2²⁰¹⁰
2^6x(8³+8¹-8⁰)=519*2²⁰¹⁰
2^6x ×(512+8-1)=519*2²⁰¹⁰
2^6x ×519=519*2²⁰¹⁰
2^6x=2²⁰¹⁰
6x=2010
x=335
2. -0,02x+7,2=4,8
0,02x=2,4
x=2,4:0,02=120
3.
0,15 m=15 cm
A=15x24/2=180 cm²
4.
Ptriunghiului ABD=48
BD=48-15x2=48-30=18
BD intersectat cu AC = O
DO=18/2=9
AO=√15²-9²=√225-81=√144=12
AC=12x2=24
A=(18x24)/2=216
6.
AB/AC=2/5
AB+AC=35
AC=5AB/2
AB+5AB/2=35
2AB+5AB=70
AB=10
AC=5x10/2=25
Aria=10x25/2=125 cm²
7.
√ab=√[(√5-2)(√6+√5)(√3-√2)(√5+2)(√6-√5)(√3+√2)]=
=√(5-4)(6-5)(3-2)=√1=1
8.
-4x+5=-7
-4x=-12
x=3
9.
n=(√3+√12+√27+√48+...+√300)/√75=
=√3(1+2+3+4+....+10)/5√3=
=[10(10+1)/2]/5=
=5×11/5=11
