F(x) = 4x - 9
let f(x) = y, this implies that x = f⁻¹(y)
y = 4x - 9 Let us solve for x.
4x - 9 = y
4x = y + 9
x = (y + 9)/4
Recall that x = f⁻¹(y),
x = (y + 9)/4
f⁻¹(y) = (y + 9)/4
That means that for f⁻¹(x)
f⁻¹(x) = (x + 9)/4
Hope this explains it.
-2/5=-.4
-7=-7
These two are repeating decimals.
3/9=.3333334
11/12=.9166667
Answer:
a). 59.049°C
b). 2.1179 seconds
Step-by-step explanation:
Expression representing the final temperature after decrease in temperature of the metal from 100°C to T°C is,
T = 
where x = duration of cooling
a). Temperature when x = 5 seconds
T = 100(0.9)⁵
= 59.049
≈ 59.049°C
b). If the temperature of the metal decreases from 100°C to 80°C
Which means for T = 80°C we have to calculate the duration of cooling 'x' seconds
80 = 
0.8 = 
By taking log on both the sides
log(0.8) =log[
]
-0.09691 = x[log(0.9)]
-0.09691 = -0.045757x
x = 
x = 2.1179
x ≈ 2.1179 seconds
Hello,
f(π/2)=4*sin(π/2)-2=4*1-2=2
f(0)=4*sin(0)-2=0-2=-2
rate=(2+2)/(π/2-0)=8/π
Answer D