Question 4. Find the Zero of the Polynomial in Each of the Follow Exercise 2.2 Chapter 2 Polynomial Maths Class 9

Question 4. Find the zero of the polynomial in each of the following cases:
(i) p(x) = x + 5            (ii) p(x) = x – 5           (iii) p(x) = 2x + 5        (iv) p(x) = 3x – 2
(v) p(x) = 3x               (vi) p(x) = ax, a ≠ 0    (vii) p(x) = cx + d, c ≠ 0, c, d are real numbers.

Solution: (i)p(x) = x + 5            
Plug p(x) = 0 we get
=>x+5 =0
=>  x = - 5
-5 is zero of the polynomial

(ii) p(x) = x – 5          
Plug p(x) = 0 we get
=>x - 5 = 0
=> x = 5 
5 is zero of the polynomial

(iii) p(x) = 2x + 5       
Plug p(x) = 0 we get
=>2x+5 =0
=> 2x = - 5
=> x= -5/2
-5/2is zero of the polynomial

(iv) p(x) = 3x – 2
Plug p(x) = 0 we get
=>3x-2=0
=>3x =2
=> x = 2/3
2/3 is zero of the polynomial

 (v) p(x) = 3x
Plug p(x) = 0 we get
=>3x=0
=> x= 0/3
=> x=0                       
0 is zero of the polynomial

 (vi) p(x) = ax, a ≠ 0  
Plug p(x) = 0 we get
=>ax=0
=> x =0/a
=> x = 0
0 is zero of the polynomial

 (vii) p(x) = cx + d, c ≠ 0, c, d are real numbers.
Plug p(x) = 0 we get
=>cx +d = 0
=> cx = - d
=> x = -d/c
-d/c is zero of the polynomial