Question

2. Find the product x' x (2x - 5y7). Also verify the result for x = - 1 and y = 2.​

Answer 1

Step-by-step explanation:

3x

3

y

2

×(2x−3y)

=3x

3

y

2

⋅2x−3x

3

y

2

⋅3y

=6x

4

y

2

−9x

3

y

3

Now, for x=−1,y=2, we have

L.H.S.-

3x

3

y

2

×(2x−3y)

=3(−1)

3

(2)

2

(2⋅(−1)−3⋅(2))

=3⋅(−1)⋅4×(−2−6)

=(−12)×(−8)

=96

R.H.S.-

6x

4

y

2

−9x

3

y

3

=6(−1)

4

(2)

2

−9(−1)

3

(2)

3

=6⋅1⋅4−9⋅(−1)⋅8

=24+72

=96

∵ L.H.S. = R.H.S.

Hence verified.

Answer 2

Answer:

3x  3  y  2  ×(2x−3y)

Step-by-step explanation:

=3x  3  y  2  ⋅2x−3

=6x  4  y  2  −9x  3  y  3x  3  y  2  ⋅3y

Now, for x=−1,y=2, we have

L.H.S.

-3x  3  y  2  ×(2x−3y)

=3(−1)  3 (2)  2  (2⋅(−1)−3⋅(2))

=3⋅(−1)⋅4×(−2−6)

=(−12=x(−8)

= 96

R.H.S.-

6x  4y  2  −9x  3  y  3

=6(−1)  4  (2)  2  −9(−1) 3  (2)  3

=6⋅1⋅4−9⋅(−1)⋅8

=24+72

=96

∵ L.H.S. = R.H.S.

Hence verified.