1) 0,5*74,8*2=(0,5*2)*74,8=1*74,8=74,8
2) 0,25*3,67*0,4=(0,25*0,4)*3,67=0,1*3,67=0,367
3)0,42*5,19+5,19*0,58=(0,42+0,58)*5,19=1*5,19=5,19
4)62,9*1,8-62,7*1,8=(62,9-62,7)*1,8=0,2*1,8=0,36.
Интеграл (x^3dx)/(x^4+1)=1/4ln|x^4+1|+C
(2х+3х)/2=24
5х/2=24
5х=48
х=9.6
9.6*2=19.2дм
9.6*3=28.8дм
ctg²a+1=1/sin²a
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