Question: 4 – Find the zero of the polynomial in each of the following cases:

(i) p(x) = x + 5

**Answer:**To find the zero of the polynomial, we equate the given polynomial with zero.

Let, x + 5 = 0

Then, x = - 5

Thus, - 5 is the zero of the polynomial.

(ii) p(x) = x – 5

**Answer:** Given, p(x) = x – 5

Let, x – 5 = 0

Then, x = 5

Thus, 5 is the zero of the polynomial.

(iii) p(x) = 2x + 5

**Answer:** Given, p(x) = 2x + 5

Let, 2x + 5 = 0

Or, 2x = - 5

Or, x = - 5/2

Thus, - 5/2 is the zero of the polynomial

(iv) p(x) = 3x – 2

**Answer:** Given, p(x) = 3x – 2

Let, 3x – 2 = 0

Or, 3x = 2

Or, x = 2/3

Thus, 2/3 is the zero of the polynomial.

(v) p(x) = ax, a ≠ 0

**Answer:** Given, p(x) = ax, a≠ 0

Let, p(x) = 0

Or, ax = 0

Or, x = 0/a

Or, x = 0

Therefore, 0 is the zero of the given polynomial.

(vi) p(x) = cx + d, c≠ and c , d are real numbers

**Answer:** Given, p(x) = cx + d, c ≠ 0

Let, p(x) = 0

Or, cx + d = 0

Or, cx = - d

Or, x = - d/c

Here, - d/c is zero of the given polynomial.

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