Advertisements
Advertisements
प्रश्न
Evaluate: (2x – 5y)(2x + 3y) for x = 2 and y = 3.
Advertisements
उत्तर
(2x – 5y) (2x + 3y)
= 2x × 2x − 5y × 2x + 2x × 3y − 5y × 3y
= 4x2 − 10xy + 6xy − 15y2
Hence, x = 2 and y = 3
4x2 − 10xy + 6xy − 15y2
= 4(2)2 − 10(2)(3) + 6(2)(3) − 15(3)2
= 16 − 60 + 36 − 135
= 52 − 195
= −143
APPEARS IN
संबंधित प्रश्न
Multiply: 6x3 − 5x + 10 by 4 − 3x2
Multiply: 2y − 4y3 + 6y5 by y2 + y − 3
Multiply:
5p2 + 25pq + 4q2 by 2p2 − 2pq +3q2
Simplify : (7x – 8) (3x + 2)
Simplify: (5a + 5b – c) (2b – 3c)
The adjacent sides of a rectangle are x2 – 4xy + 7y2 and x3 – 5xy2. Find its area.
The base and the altitude of a triangle are (3x – 4y) and (6x + 5y) respectively. Find its area.
Find the value of (3x3) × (-5xy2) × (2x2yz3) for x = 1, y = 2 and z = 3.
Multiply and then verify :
−3x2y2 and (x – 2y) for x = 1 and y = 2.
Simplify : (5 – x) (6 – 5x) (2 -x).
