bonjour
f (x) = √x + 1
f 4) = √4 + 1 = 3
f ( 10.24) = √10.24 + 1 = 3.2 + 1 = 4.2
f ( 16)= √16 + 1 = 5
f ( 20.25) = √20.25 + 1 = 5.5
√x + 1 = 5
√x = 4
x = 16
√x + 1 = 4.2
√x = 3.2
x = 10.24
f ( 4.41 ) = √4.41 + 1 = 3.1
f ( 1310.44 ) = √ 1310.44 + 1 = 37.2