Question

B(y)=2y³+4y²+10y-6
D(y)=-5y²+8
1. B(y)+D(y)
2. [D(y)]²
3.B(-1)

Answer 1

Explicație pas cu pas:

1. B(y) + D(y) = 2y³+4y²+10y-6 + (-5y²+8)

=2y³+4y²+10y-6-5y²+8 = 2y³-y²+10y+2

2.[D(y)]² = (-5y²+8)² = (8-5y²)² = 64-80y²+25y⁴

3.B(-1) = 2×(-1)³+4×(-1)²+10×(-1)-6 = -2+4-10-6=2-16=-14

Answer 2

B(y) = 2y³ + 4y² + 10y - 6

D(y) = -5y² + 8

1. B(y) + D(y) = 2y³ + 4y² + 10y - 6 + ( -5y² + 8 ) =

= 2y³ + 4y² + 10y - 6 -5y² + 8 =

= 2y³ - y² + 10y + 2

B(y) + D(y) = 2y³ - y² + 10y + 2

2. [D(y)]² = ( -5y² + 8 )² = 25y⁴ - 80y² + 64

[D(y)]² = 25y⁴ - 80y² + 64

3. B(-1) = 2 · (-1)³ + 4 · (-1)² + 10 · (-1) - 6

= 2 · (-1) + 4 · 1 - 10 - 6

= -2 + 4 - 16 = - 14

B(-1) = -14