(f+g)(3)=f(3)+g(3)
f(x)=7 so f(3)=7
g(x)=x+5 so g(3)=3+5=8
(f+g)(3)=f(3)+g(3)=7+8=15
Answer:

Step-by-step explanation:
La función es

Diferenciando con respecto a
obtenemos

Igualar con cero

Doble derivada de la función

Entonces, la función es máxima cuando el número de unidades vendidas,
,
Answer:11
Step-by-step explanation:
Boys : girls=7:1
Sum of ratio=7+1=8
Let them number of girls be y
Then they number of boys=y+66
Total number of pupils=y+y+66
Total number of pupils=2y+66
Number of girls=(girls ratio)/(sum of ratio) x (total number of pupils)
y=1/8 x (2y+66)
Cross multiply
y x 8=2y + 66
8y=2y + 66
Collect like terms
8y-2y=66
6y=66
Divide both sides by 6
6y/6=66/6
y=11
The number of girls is 11
Answer:
an = 1/2 (n) (n+1)
Step-by-step explanation:
1,3,6,10,.........
3-1=2
6-3=3
Each term is different so there is no common difference. It is not an arithmetic sequence
3/1=3
6/3 =2
Each term is different so there is no common ratio. It is not a geometric sequence
1 3 6 10
+2 +3 +4
a1 = 1
a2 = 3
a3 = 6 = 2*3
a4 = 10 = 2*5