А+970=69х32
а+970=2208
а=2208-970
а=1238
-------------------
1238+970+69х32
1238=1238
Ответ: а=1238
2arcctg1=2*π/4=π/2
arcsin1=π/2
arcctg0=π/2
cos(2arcctg1-arcsin1+arcctg0)=cos(π/2-π/2+π/2)=cos(π/2)=0
47,5x+0,3x-2,4=89,6
47,8x-2,4=89,6
47,8x=89,6+2,4
47,8x=92
221
x=1 ---
239