X2-7x-44-x2-9=21
7x=74
x=74/7
x=10 4/7
<span>cos x(sin x-cos x)=0
1)cos x=0
x =</span>π/2+πk<span>, k ∈ Z
</span>2)sin x-cos x=0 (разделим левую и правую часть на cos x≠0)
tg x-1=0
tg x=1
<span>x=π/4+πk, k ∈ Z
Ответ:</span>x =π/2+πk,x=π/4+πk, k ∈ Z
0,013 = 13/1000
( 0,013 )^ - 1 = 1000/13 = 76 12/13
76 12/13 > 1
Ответ ( 0,013 )^ - 1 > 1
1.2х+0.6 = -5.4х + 7.2
1.2х + 5.4х = 7.2 - 0.6
6.6х = 6.6
х =1
10/3-4/3*16-/3*9=
10/3-4*4/3-3/3=
10/3-16/3-3/3=
-9/3