Question

срез знаний по алгебре​

Answer 1

Ответ:

1)(1 3/5-3/4):(1 3/20+2,6)+58/75=(1,6-0,75):(1,15+2,6)+58/75=0,85:3,75+58/75=17/20•4/15+58/75=17/75+58/75=75/75=1

2)a)3x+2(11-x)=7-(x-3); 3x+22-2x=7-x+3;

2x=-12; x=-6

3)x²-4√2x+4; D=32-16=16; x1=(4√2-4)/2=2(√2-1)

x2=(4√2+4)/22(√2+1)

4) α°=2π/360°•α; 1°=2π•1°360°=π/180

5°=2π•5°/360=π/36

30°=π•30/180=π/6

-135°=π•(-135)/180=-3π/4

225°=π•225/180=5π/4

-162°=π•(-162)/180=9π/10

5)a)Sinα•Cosα(Tgα+Ctgα)=Sinα•Sinα•Cosα/Cosα+Sinα•Cosα•Cosβ/Sinα=Sin²α+Cos²α=1

б) Sin²α+Cos²α+Tgα•Ctgα=1+1=2

в)Ctg²45°-Tg²45°+3/4Tg²30°+Cos²30°-Sin30°=1-1+3/4•3/9+3/4-1/2=1/4+3/4-1/2=1-1/2=1/2