Решение
1) 5sinx - 5 = 0
sinx = 1
x = π+ 2πk, k ∈ Z
2) tgx - √3 = 0
tgx = √3
x = arctg√3 + πn, n ∈ Z
x = π/3 + πn, n ∈ Z
Ответ:
√21-√8√5+1√5-2=√21-√8(5+1)*(5-2)=√21-√8*6*3=√21-√144=√21-12
3с^2* (5с-8)=15c^3-24c^2
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______(2,5)_____________(2,6)__________