1)64ˇ(㏒8 √3)=(8²)ˇ(㏒8 √3)=8ˇ(2(㏒8 √3)=8ˇ(log8 (√3)²=
=8ˇlog8 3=3
2)25ˇx-3.5ˇx+2=0
(5²)ˇx-3.5ˇx+2=0
(5ˇx)²-3.5ˇx+2=0
5ˇx=z
z²-3z+2=0
(z-1)(z-2)=0
a)z-1=0,z=1, 5ˇx=1,5ˇx=5ˇ0,x=0
b)z-2=0,z=2,5ˇx=2, log(5ˇx)=log 2, x.log 5=log 2, x=log 2/log 5
3)sin α=0,8. cosα=?,tgα=?, α∈(π/2,π)
sin²α+cos²α=1, cos²α=1-0,8²=1-0,64=0,36,/cosα/=0,6
cosα=-0,6 (potomy, čto α∈(π/2,π)
tgα=sinα/cosα=0,8/(-0,6)=-4/3
tgα=-4/3
4)log6 (5x-1)≤2log6 3 +1, 5x-1 bolše čem 0, x bolše čem 1/5
log6 (5x-1)≤log6 3² + log6 6
log6 (5x-1)≤log6 9 + log6 6
log6 (5x-1)≤log6 (9.6)
log6 (5x-1)≤log6 54
5x-1≤54, 5x≤55, x≤11
x≤11 ∧ x bolše čem 1/5
x∈ (1/5, 11/