**Chapter 3 Polynomials Practice Set 3.4**

Chapter 3 Polynomials Practice Set 3.4

**Question 1.For x = 0, find the value of the polynomial x ^{2} â€“ 5x + 5.Solution:**

p(x) = x

^{2}â€“ 5x + 5

Put x = 0 in the given polynomial.

âˆ´ P(0) = (0)

^{2}â€“ 5(0) + 5

= 0 â€“ 0 + 5

âˆ´ p(0) = 5

**Question 2.If p(y) = y ^{2} â€“ 3âˆš2 + 1, then find p( 3âˆš2 ).Solution:**

p(y) = y

^{2}â€“ 3âˆš2 y + 1

Putp= 3âˆš2 in the given polynomial.

âˆ´ p( 3âˆš2 ) = (3âˆš2 )

^{2}â€“ 3âˆš2 (3âˆš2 ) + 1

= 9 x 2 â€“ 9 x 2 + 1

= 18 â€“ 18 + 1

âˆ´ p( 3âˆš2 ) = 1

**Question 3.If p(m) = m ^{3} + 2m^{2} â€“ m + 10, then P(a) + p(-a) = ?Solution:**

p(m) = m

^{3}+ 2m

^{2}â€“ m + 10

Put m = a in the given polynomial.

âˆ´ p(a) = a

^{3}+ 2a

^{2}â€“ a + 10 â€¦(i)

Put m = -a in the given polynomial.

p(-a) = (-a)

^{3}+ 2(-a)

^{2}â€“ (-a) +10

âˆ´ p (-a) = -a

^{3}+ 2a

^{2}+ a + 10 â€¦(ii)

Adding (i) and (ii),

p(a) + p(-a) = (a

^{3}+ 2a

^{2}â€“ a + 10) + (-a

^{3}+ 2a

^{2}+ a + 10)

âˆ´ p(a) + p(-a) = 4a^{2} + 20

**Question 4.If p(y) = 2y ^{3} â€“ 6y^{2} â€“ 5y + 7, then find p(2).Solution:**

p(y) = 2y

^{3}â€“ 6y

^{2}â€“ 5y + 7

Put y = 2 in the given polynomial.

âˆ´ p(2) = 2(2)

^{3}â€“ 6(2)

^{2}â€“ 5(2) + 7

= 2 x 8 â€“ 6 x 4 â€“ 10 + 7

= 16 â€“ 24 â€“ 10 + 7

âˆ´ P(2) = -11