The complex number z = x + iy satisfies the condition ∣ z + 1 ∣ = 1, then z lies on 

In Class 11th, Chapter 4 of the NCERT Maths book focuses on Complex Numbers and Quadratic Equations. This chapter starts by introducing complex numbers, which are numbers that include both real and imaginary parts. Students learn how to perform various operations on complex numbers, such as addition, subtraction, multiplication, and division. The chapter also covers the geometric representation of these numbers, as well as their modulus and argument. Quadratic equations are explored with different solving techniques, including factoring, completing the square, and applying the quadratic formula. Finally, the chapter delves into the nature of roots and discriminants.