We calculate for the actual length of the thing in the model that measures 25.25 by multiplying this value by the scale factor. That is,
(25.25 cm) x (55.5 m / 15 cm) = 93.425 m
Therefore, the real dimension of the object is approximately 93.43 m.
![\bf \begin{cases} x=3\implies &x-3=0\\ x=1+3i\implies &x-1-3i=0\\ x=1-3i\implies &x-1+3i=0 \end{cases} \\\\[-0.35em] ~\dotfill\\\\ (x-3)(x-1-3i)(x-1+3i)=0 \\\\\\ (x-3)\underset{\textit{difference of squares}}{([x-1]-3i)([x-1]+3i)}=0\implies (x-3)([x-1]^2-[3i]^2)=0 \\\\\\ (x-3)([x^2-2x+1]-[3^2i^2])=0\implies (x-3)([x^2-2x+1]-[9(-1)])=0](https://tex.z-dn.net/?f=%5Cbf%20%5Cbegin%7Bcases%7D%20x%3D3%5Cimplies%20%26x-3%3D0%5C%5C%20x%3D1%2B3i%5Cimplies%20%26x-1-3i%3D0%5C%5C%20x%3D1-3i%5Cimplies%20%26x-1%2B3i%3D0%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%28x-3%29%28x-1-3i%29%28x-1%2B3i%29%3D0%20%5C%5C%5C%5C%5C%5C%20%28x-3%29%5Cunderset%7B%5Ctextit%7Bdifference%20of%20squares%7D%7D%7B%28%5Bx-1%5D-3i%29%28%5Bx-1%5D%2B3i%29%7D%3D0%5Cimplies%20%28x-3%29%28%5Bx-1%5D%5E2-%5B3i%5D%5E2%29%3D0%20%5C%5C%5C%5C%5C%5C%20%28x-3%29%28%5Bx%5E2-2x%2B1%5D-%5B3%5E2i%5E2%5D%29%3D0%5Cimplies%20%28x-3%29%28%5Bx%5E2-2x%2B1%5D-%5B9%28-1%29%5D%29%3D0)
[ correction added, Thanks to @stef68 ]
![\bf (x-3)([x^2-2x+1]+9)=0\implies (x-3)(x^2-2x+10)=0 \\\\\\ x^3-2x^2+10x-3x^2+6x-30=0\implies x^3-5x^2+16x-30=f(x) \\\\\\ \stackrel{\textit{applying a translation with a -2f(x)}}{-2(x^3-5x^2+16x-30)=f(x)}\implies -2x^3+10x^2-32x+60=f(x)](https://tex.z-dn.net/?f=%5Cbf%20%28x-3%29%28%5Bx%5E2-2x%2B1%5D%2B9%29%3D0%5Cimplies%20%28x-3%29%28x%5E2-2x%2B10%29%3D0%20%5C%5C%5C%5C%5C%5C%20x%5E3-2x%5E2%2B10x-3x%5E2%2B6x-30%3D0%5Cimplies%20x%5E3-5x%5E2%2B16x-30%3Df%28x%29%20%5C%5C%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7Bapplying%20a%20translation%20with%20a%20-2f%28x%29%7D%7D%7B-2%28x%5E3-5x%5E2%2B16x-30%29%3Df%28x%29%7D%5Cimplies%20-2x%5E3%2B10x%5E2-32x%2B60%3Df%28x%29)
x = 9.21° or x = 22.5°
cot²2x – 4cot2x + 3 = 0
Let cot2x = y
y² - 4y + 3 = 0
Factorizing, we have
y² - y - 3y + 3 = 0
y(y - 1) -3(y - 1) = 0
(y - 1)(y - 3) = 0
y - 1 = 0 or y - 3 = 0
y = 1 or y = 3
Since cot2x = y
cot2x = 1 or cot2x = 3
1/tan2x = 1 or 1/tan2x = 3
tan2x = 1 or tan2x = 1/3
2x = tan⁻¹(1) or 2x = tan⁻¹(1/3)
2x = 45° or 2x = 18.43°
x = 45°/2 or x = 18.43°/2
x = 22.5° or x = 9.21°
So, x = 9.21° or x = 22.5°
Learn more about cotx here:
brainly.com/question/15546709
