2x - 8 = 0
2x = 8
x = 4
4x + 3 = 0
4x = - 3
x = - 3 /4 = - 0,75
D=5
a₁=-4,8
S₁₅=n*(a₁+a₁₅)/2=15*(-4,8-4,8+5*14)/2=15*(-9,6+70)/2=(70*15-15*9,6)/2=35*15-15*4,8=15(35-4,8)=15*30,2=453
(n²+n)/2=55
n²+2=55*2
n²+n=110
n²+n-110=0
D=441=21²
n₁=(-1+21)/2=10
n₂=(-1-21)/2=-11∉N
n=10
(1/8)³=(2⁻³)³=2⁻⁹ 2¹/₅=2⁰₎²
(1/4)³=(2⁻²)³=2⁻⁶
㏒₂2⁻⁹ * 2⁻⁰₎⁵ :2⁻⁶:2⁰₎² = ㏒₂2⁻⁹ ⁺⁽⁻⁰₎⁵⁾ ⁻⁽⁻⁶⁾⁻⁰₎² = ㏒₂2⁻⁹ ⁻⁰₎⁵ ⁺⁶ ⁻⁰₎² = ㏒₂2⁻³₎⁷=
=-3,7*㏒₂2 = -3.7*1= -3,7
(6,8-4,7)/1,4 = 2,1/1,4 = 1,5.