Answer:
Step-by-step explanation:
cos (x/2)=cos x+1
cos (x/2)=2cos ²(x/2)
2 cos²(x/2)-cos (x/2)=0
cos (x/2)[2 cos (x/2)-1]=0
cos (x/2)=0=cos π/2,cos (3π/2)=cos (2nπ+π/2),cos(2nπ+3π/2)
x/2=2nπ+π/2,2nπ+3π/2
x=4nπ+π,4nπ+3π
n=0,1,2,...
x=π,3π
or x=180°,540°,...
180°∈[0,360]
so x=180°
or
2cos(x/2)-1=0
cos (x/2)=1/2=cos60,cos (360-60)=cos 60,cos 300=cos (360n+60),cos (360n+300)
x/2=360n+60,360n+300
x=720n+120,720n+300
n=0,1,2,...
x=120,300,840,1020,...
only 120° and 300° ∈[0,360°]
Hence x=120°,180°,300°
Answer:
r≈2.36cm
Step-by-step explanation:
Answer:
Elementos y propiedades del paralelogramo
Lados: el paralelogramo tiene cuatro lados, siendo iguales y paralelos dos a dos (a y b). Ángulos: los ángulos interiores son iguales dos a dos, siendo iguales los ángulos no consecutivos (α y β). Como en todo cuadrilátero, sus ángulos interiores suman 360° (2α + 2β = 360°)
Step-by-step explanation:
Elements and properties of the parallelogram
Sides: the parallelogram has four sides, two by two (a and b) being equal and parallel. Angles: the interior angles are equal two by two, the non-consecutive angles (α and β) being equal. As in any quadrilateral, its interior angles add up to 360 ° (2α + 2β = 360 °) (English version lol)
Answer:
Step-by-step explanation:
We have to find the equation of plane that is parallel to the vectors
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The plane also passes through the point (2,0,-1).
Hence, the equation of plane s given by:
![\displaystyle\left[\begin{array}{ccc}x-2&y-0&z+1\\3&0&3\\0&1&3\end{array}\right]\\\\=(x-2)(0-3) - (y-0)(9-0) + (z+1)(3-0)\\=-3(x-2)-9y+3(z+1)\\\Rightarrow -3x + 6 - 9y + 3z + 3 = 0\\\Rightarrow 3x + 9y -3z -9 = 0\\\Rightarrow x + 3y -z - 3 = 0](https://tex.z-dn.net/?f=%5Cdisplaystyle%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dx-2%26y-0%26z%2B1%5C%5C3%260%263%5C%5C0%261%263%5Cend%7Barray%7D%5Cright%5D%5C%5C%5C%5C%3D%28x-2%29%280-3%29%20-%20%28y-0%29%289-0%29%20%2B%20%28z%2B1%29%283-0%29%5C%5C%3D-3%28x-2%29-9y%2B3%28z%2B1%29%5C%5C%5CRightarrow%20-3x%20%2B%206%20-%209y%20%2B%203z%20%2B%203%20%3D%200%5C%5C%5CRightarrow%203x%20%2B%209y%20-3z%20-9%20%3D%200%5C%5C%5CRightarrow%20x%20%2B%203y%20-z%20-%203%20%3D%200)
It is the required equation of plane.