А и в катеты
SΔ=(1/2)а*в
60=(1/2)а*в, а*в=120
{а+в=23 {а=23-в
а*в=120 (23-в)*в=120
в²-23в+120=0
в₁=8, в₂=15
{а₁=23-8 , {а₁=15
в₁=8 в₁=8
{а₂=8
в₂=15
ответ: катеты 8см и 15 см
Там нужно домножить на 2 , затем раскрыть по формуле понижения степени
![3sin^2(\frac{x}{2})+sin(\frac{x}{2})*sin(\frac{\pi}{2}-\frac{x}{2})=2 \\ 3sin^2(\frac{x}{2})+sin(\frac{x}{2})*cos(\frac{x}{2})=2\\ 6sin^2(\frac{x}{2})+sinx=4\\ 6*(\frac{1-cosx}{2})+sinx=4\\ 3(1-cosx)+sinx=4\\ 3-3cosx+sinx=4\\ sinx-3cosx=1\\ \sqrt{1-cos^2x}-3cosx=1\\ cosx=t\\ \sqrt{1-t^2}-3t=1\\ \sqrt{1-t^2}=1+3t\\ 1-t^2=(1+3t)^2\\ 1-t^2=1+6t+9t^2\\ 10t^2+6t=0\\ 2t(5t+3)=0\\ t=0\\ cosx=0\\ x=2*pin+\frac{\pi}{2}\\](https://tex.z-dn.net/?f=3sin%5E2%28%5Cfrac%7Bx%7D%7B2%7D%29%2Bsin%28%5Cfrac%7Bx%7D%7B2%7D%29%2Asin%28%5Cfrac%7B%5Cpi%7D%7B2%7D-%5Cfrac%7Bx%7D%7B2%7D%29%3D2%20%5C%5C%0A%203sin%5E2%28%5Cfrac%7Bx%7D%7B2%7D%29%2Bsin%28%5Cfrac%7Bx%7D%7B2%7D%29%2Acos%28%5Cfrac%7Bx%7D%7B2%7D%29%3D2%5C%5C%206sin%5E2%28%5Cfrac%7Bx%7D%7B2%7D%29%2Bsinx%3D4%5C%5C%206%2A%28%5Cfrac%7B1-cosx%7D%7B2%7D%29%2Bsinx%3D4%5C%5C%203%281-cosx%29%2Bsinx%3D4%5C%5C%203-3cosx%2Bsinx%3D4%5C%5C%20sinx-3cosx%3D1%5C%5C%20%5Csqrt%7B1-cos%5E2x%7D-3cosx%3D1%5C%5C%20cosx%3Dt%5C%5C%20%5Csqrt%7B1-t%5E2%7D-3t%3D1%5C%5C%20%5Csqrt%7B1-t%5E2%7D%3D1%2B3t%5C%5C%201-t%5E2%3D%281%2B3t%29%5E2%5C%5C%201-t%5E2%3D1%2B6t%2B9t%5E2%5C%5C%2010t%5E2%2B6t%3D0%5C%5C%202t%285t%2B3%29%3D0%5C%5C%20t%3D0%5C%5C%20cosx%3D0%5C%5C%20x%3D2%2Apin%2B%5Cfrac%7B%5Cpi%7D%7B2%7D%5C%5C%20)
Ответ: 2
Объяснение:
v(t)=s'(t)=2t+1, a(t)=v'(t)=2
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