Punjab State Board PSEB 8th Class Maths Book Solutions Chapter 9 ਬੀਜਗਣਿਤਕ ਵਿਅੰਜਕ ਅਤੇ ਤਤਸਮਕ Ex 9.4 Textbook Exercise Questions and Answers.
PSEB Solutions for Class 8 Maths Chapter 9 ਬੀਜਗਣਿਤਕ ਵਿਅੰਜਕ ਅਤੇ ਤਤਸਮਕ Exercise 9.4
1. ਦੋ ਪਦੀਆਂ ਨੂੰ ਗੁਣਾ ਕਰੋ :
ਪ੍ਰਸ਼ਨ (i).
(2x + 5) ਅਤੇ (4x – 3)
ਹੱਲ:
(2x + 5) × (4x – 3)
= 21 × (4x – 3) +5 (4x – 3)
= 2x × 4x – 2x × 3 + 5 × 4x – 5 × 3
= 8x2 – 6x + 20x – 15
= 8x2 + 14 – 15.
ਪ੍ਰਸ਼ਨ (ii).
(y – 8) ਅਤੇ (3y – 4)
ਹੱਲ:
(y – 8) × (3y – 4)
= y (3y – 4) – 8 × (3y – 4)
= 3y2 – 4y – 24y + 32
= 3y2 – 28y + 32.
ਪ੍ਰਸ਼ਨ (iii).
(2.5l – 0.5m) ਅਤੇ (2.5l + 0.5m)
ਹੱਲ:
(2.5l – 0.5m) × (2.5l + 0.5m)
= 2.5l × (2.5l + 0.5m) – 0.5m (2.5l + 0.5m)
= 6.25l2 + 1.25lm – 1.25lm – 0.25m2
= 6.25l2 – 0.25m2.
ਪ੍ਰਸ਼ਨ (iv).
(a + 3b) ਅਤੇ (x + 5)
ਹੱਲ:
(a + 3b) × (x + 5)
= a × (x + 5) + 3b × (x + 5)
= ax + 5a + 3bx + 15b
ਪ੍ਰਸ਼ਨ (v).
(2pq + 3q2) ਅਤੇ (3pq – 2q2)
ਹੱਲ:
(2pq + 3q2) × (3pq – 2q2)
= 2pq × (3pq – 2q2) + 3q2 × (3pq – 2q2)
= 6p2q2 – 4pq3 + 9pq3 – 6q4
= 6p2q2 + 5pq3 – 6q4.
ਪ੍ਰਸ਼ਨ (vi).
(\(\frac{3}{4}\)a2 + 3b2) ਅਤੇ 4(a2 – \(\frac{2}{3}\)b2)
ਹੱਲ:
(\(\frac{3}{4}\)a2 + 3b2) × (4a2 – \(\frac{8}{3}\)b2)
= \(\frac{3}{4}\)a2 × (4a2 – \(\frac{8}{3}\)b2) + 3b2 × (4a2 – \(\frac{8}{3}\)b2)
= 3a4 – 2a2b2 + 12a2b2 – 8b4
= 3a4 + 10a2b2 – 8b4
2. ਗੁਟਨਫਲ ਪਤਾ ਕਰੋ :
ਪ੍ਰਸ਼ਨ (i).
(5 – 2x) (3 + x)
ਹੱਲ:
(5 – 2x) (3 + x)
= 5 × (3 + x) – 2x × (3 + x)
= 15 + 5x – 6x – 2x2
= 15 – x – 2x2
ਪ੍ਰਸ਼ਨ (ii).
(x + 7y) (7x – y)
ਹੱਲ:
(x + 7y) (7x – y)
= x × (7x – y) + 7y × (7x – y)
= 7x2 – xy + 49xy – 7y2
= 7x2 + 48xy – 7y2
ਪ੍ਰਸ਼ਨ (iii).
(a2 + b)(a + b2)
ਹੱਲ:
(a2 + b) (a + b2) for a = 3, b = – 3
= a2(a + b2) + b (a + b2)
= a3 + a2b2 + ab + b3
ਪ੍ਰਸ਼ਨ (iv).
(p2 – q2) (2p + q)
ਹੱਲ:
(p2 – q2) (2p + q) for p = 1, q = -2
= p2(2p +q) – q2(2p + q)
= 2p3 + p2q – 2pq2 – q3
3. ਸਨਲ ਕਰੋ :
ਪ੍ਰਸ਼ਨ (i).
(x2 – 5) (x + 5) + 25
ਹੱਲ:
(x2 – 5) (x + 5) + 25
= x2 (x + 5) – 5 (x + 5) + 25
= x3 + 5x2 – 5x – 25 + 25
= x3 + 5x2 – 5x.
ਪ੍ਰਸ਼ਨ (ii).
(a2 + 5) (b3 + 3) + 5
ਹੱਲ:
(a2 + 5) (b3 + 3) + 5
= a2(b3 + 3) + 5 (b3 + 3) + 5
= a2b3 + 3a2 + 5b3 + 15 + 5
= a2b3 + 3a2 + 5b3 + 20.
ਪ੍ਰਸ਼ਨ (iii).
(t + s2) (t2 – s)
ਹੱਲ:
(t + s2) (t2 – s)
= t(t2 – s) + s2(t2 – s)
= t3 – t2 + s2t2 – s3.
ਪ੍ਰਸ਼ਨ (iv).
(a + b) (c – d) + (a – b) (c + d) + 2(ac + bd)
ਹੱਲ:
(a + b) (c – d) + (a – b) (c + d) + 2 (ac + bd)
= a (c – d) + b (c – d) + a (c + d) – b (c + d) + 2ac + 2bd
= ac – ad + bc – bd + ac + ad – bc – bd + 2ac + 2bd
= 4ac.
ਪ੍ਰਸ਼ਨ (v).
(x + y) (2x + y) + (x + 2y) (x – y)
ਹੱਲ:
(x + y) (2x + y) + (x + 2y) (x – y)
= x(2x + y) + y (2x + y) +x (x – y) + 2y (x – y)
= 2x2 + xy + 2xy + y2 + x2 – xy + 2xy – 2y2
= 3x2 + 4xy – y2
ਪ੍ਰਸ਼ਨ (vi).
(x + y) (x2 – xy + y2)
ਹੱਲ:
(x + y) (x2 – xy + y2)
= x (x2 – xy + y2) + y (x2 – xy + y2)
= x3 – x2y + xy2 + yx2 – xy2 + y3
= x3 + y3.
ਪ੍ਰਸ਼ਨ (vii).
(1.5x – 4y) (1.5x + 4y + 3) – 4.5x + 12y
ਹੱਲ:
(1.5x – 4y) (1.5x + 4y + 3) – 4.5x + 12y
= 1.5x (1.5x + 5y + 3) – 4y (1.5x + 4y + 3) – 4.5x + 12y
= 2.25x2 + 6xy + 4.5x – 6xy – 16y2 – 12y – 4.5x + 12y
= 2.25x2 – 16y2
ਪ੍ਰਸ਼ਨ (viii).
(a + b + c)(a + b – c)
ਹੱਲ:
(a + b + c) (a + b – c)
= a (a + b – c) + b (a + b – c) + c (a + b – c)
= a2 + ab – ac + ab + b2 – bc + ac + bc – c2
= a2 + b2 – c2 + 2ab.