Question

sqrt(4-5x)*sqrt(16-x^2)=0

Answer 1

√(4-5x)*√(16-x²)=0
C.E
4-5x≥0
16-x²≥0
deci
x∈(-∞;4/5] ∩ [-4;4]=[-4;4/5]=D
rezolvand ecuatiile, obtinem
4-5x=0
x=4/5∈D
16-x²=0
x=-4∈D
x=4∉D
S={-4;4/5}