If it was in 10 years it would either be 2.6
Recall that
d/dx sech(x) = - sech(x) tanh(x)
d/dx tan⁻¹(x) = 1/(1 + x²)
Then by the chain rule,
dy/dx = - sech(x) tanh(x) / (1 + x²)
Answer:
![\large\boxed{1.\ f^{-1}(x)=\sqrt[12]{3^x}}\\\\\boxed{2.\ f^{-1}(x)=\sqrt[4]{3^x}}\\\\\ \boxed{3.\ f^{-1}(x)=\sqrt[3]{4^{7-x}}}](https://tex.z-dn.net/?f=%5Clarge%5Cboxed%7B1.%5C%20f%5E%7B-1%7D%28x%29%3D%5Csqrt%5B12%5D%7B3%5Ex%7D%7D%5C%5C%5C%5C%5Cboxed%7B2.%5C%20f%5E%7B-1%7D%28x%29%3D%5Csqrt%5B4%5D%7B3%5Ex%7D%7D%5C%5C%5C%5C%5C%20%5Cboxed%7B3.%5C%20f%5E%7B-1%7D%28x%29%3D%5Csqrt%5B3%5D%7B4%5E%7B7-x%7D%7D%7D)
Step-by-step explanation:

![2.\\y=\log_3x^4\\\\\text{Exchange x and y. Solve for y:}\\\\\log_3y^4=x\Rightarrow3^{\log_3y^4}=3^x\Rightarrow y^{4}=3^x\\\\y=\sqrt[4]{3^x}\\-------------------------](https://tex.z-dn.net/?f=2.%5C%5Cy%3D%5Clog_3x%5E4%5C%5C%5C%5C%5Ctext%7BExchange%20x%20and%20y.%20Solve%20for%20y%3A%7D%5C%5C%5C%5C%5Clog_3y%5E4%3Dx%5CRightarrow3%5E%7B%5Clog_3y%5E4%7D%3D3%5Ex%5CRightarrow%20y%5E%7B4%7D%3D3%5Ex%5C%5C%5C%5Cy%3D%5Csqrt%5B4%5D%7B3%5Ex%7D%5C%5C-------------------------)
![3.\\y=-\log_4x^3+7\\\\\text{Exchange x and y. Solve for y:}\\\\-\log_4y^3+7=x\qquad\text{subtract 7 from both sides}\\\\-\log_4 y^3=x-7\qquad\text{change the signs}\\\\\log_4y^3=7-x\Rightarrow4^{\log_4y^3}=4^{7-x}\\\\y^3=4^{7-x}\Rightarrow y=\sqrt[3]{4^{7-x}}](https://tex.z-dn.net/?f=3.%5C%5Cy%3D-%5Clog_4x%5E3%2B7%5C%5C%5C%5C%5Ctext%7BExchange%20x%20and%20y.%20Solve%20for%20y%3A%7D%5C%5C%5C%5C-%5Clog_4y%5E3%2B7%3Dx%5Cqquad%5Ctext%7Bsubtract%207%20from%20both%20sides%7D%5C%5C%5C%5C-%5Clog_4%20y%5E3%3Dx-7%5Cqquad%5Ctext%7Bchange%20the%20signs%7D%5C%5C%5C%5C%5Clog_4y%5E3%3D7-x%5CRightarrow4%5E%7B%5Clog_4y%5E3%7D%3D4%5E%7B7-x%7D%5C%5C%5C%5Cy%5E3%3D4%5E%7B7-x%7D%5CRightarrow%20y%3D%5Csqrt%5B3%5D%7B4%5E%7B7-x%7D%7D)
I'm guessing that the 2 in that is ^2? if so, it opens down.
Your answer to the first one is incorrect.
We can cut the plan into two figures, a rectangle with side lengths of 4 cm and 5 cm and a rectangle with side lengths of 1 and 2 cm.
Perimeter of a Rectangle:
P = 2(l + w)
P = 2(4 + 5)
P = 2(9)
P = 18
Perimeter of a Rectangle:
P = 2(l + w)
P = 2(2 + 1)
P = 2(3)
P = 6
Add up the perimeters:
18 + 6 = 24
So the total perimeter is 24.
For the 2nd one, your answer is also incorrect.
We multiply 5 to the perimeter of the plans:
5 * 24 = 120
Not sure what the third one is asking.
For the fourth one we just multiply 'k' to the perimeter:
24 * k = 24k