Answer:
i. 33
ii. 1488
iii. 65
Step-by-step explanation:
i. 4x² − 3y² + 5z²
Putting the values x=2, y=-1 and z=2
4(2)² − 3(-1)² + 5(2)²
4×4 − 3×(1)² + 5×(4)
(16) - (3×1) + (20)
16 - 3+ 20
36 - 3
33
ii. 3x³ − 2x(4yz+5x²)
Putting the values x=2, y=-1 and z=2
[3(2)³ − 2×2(4×(-1)×2 + 5×(2)²)]
[3(8)³ − 2×2(-8 + 5×4)]
[3 ×512 - 2×2(-8 +20)]
[1536 - 4(12)]
[1536 - 48]
1488
iii. 1−4x(yz+3xy)
Putting the values x=2, y=-1 and z=2
[1 - 4 × 2((-1)×2 + 3×2×(-1))]
[1- 8(-2 + (-6))]
[1- 8 (-2 -6)]
[1 - 8(-8)]
[1 +64]
65
