Carry out the multiplication of the expressions in each of the following pairs. (i) 4p, q + r (ii) ab, a - b (iii) a + b, 7a 2b 2
Answers
Answer:
Identify the terms, their coefficients for each of the following expressions:
(i) 5xyz2 – 3zy
(ii) 1 + x + x2
(iii) 4x2y2 – 4x2y2z2 + z2
(iv) 3 – pq + qr – rp
(v)
(vi) 0.3 a – 0.6 ab + 0.5 b
Sol. (i) 5xyz2 – 3zy
In the expression 5xyz2 – 3zy, the terms are 5xyz2 and –3zy.
coefficient of xyz2 in the term 5xyz2 is 5.
coefficient of zy in the term –3zy is –3.
(ii) 1 + x + x2
In the expression 1 + x + x2, the terms are 1, x and x2.
Coefficient of x° in the term 1 is 1.
Coefficient of x in the term x is 1.
Coefficient of x2 is the term x2 is 1.
(iii) In the expression 4x2y2 – 4x2y2z2 + z2, the terms are 4x2y2, –4x2y2z2 and z2.
Coefficient of x2y2 in the term 4x2y2 is 4.
Coefficient of x2y2z2 in the term –4x2y2z2 is –4.
Coefficient of z2 in the term z2 is 1.
(iv) 3 – pq + qr – rp
In the expression 3 – pq + qr – rp, the terms are 3, –pq, qr and –rp
Coefficient of x° in the term 3 is 3.
Coefficient pq in the term –pq is –1.
Coefficient qr in the term qr is 1.
Coefficient rp in the term –rp is 1.
(v) In the expression the terms are
Coefficient of x in the term
Coefficient of y in the term
Coefficient of xy in the term – xy is – 1.
(vi) In the expression 0.3 a, – 0.6 ab and 0.5 b
Coefficient of a in the term 0.3a is 0.3.
Coefficient of ab in the term –0.6ab is
–0.6.
Coefficient of b in the term 0.5b is 0.5.
2. Classify the following polynomials as monomials, bionomials, trinomlals. Which polynomials do not fit in any of these three categories?
x + y, 1000, x + x2 + x3 + x4, 7 + y + 5x,
2y – 3y2, 2y – 3y2 + 4y3, 5x – 4y + 3xy,
4z – 15z2,
ab + bc + cd + da, pqr, p2q + pq2, 2p + 2q.
Sol. The given polynomials are classified as under:
Monomials: 1000, pqr
Binomials: x + y, 2y – 3y2, 4z – 15z2, p2q + pq2, 2p + 2q.
Trinomials: 7 + y + 5x, 2y – 3y2 + 4y3,
5x – 4y + 3xy.
Polynomials that do not fit in any categories:
x + x2 + x3 + x4, ab + bc + cd + da
Answer:
x = 1 8= z + X .......... !!!!!!!!!!!!!