<span>f′(x)=<span><span>(<span><span>sin<span>(x)</span>+cos<span>(x)/</span></span><span>sin<span>(x)</span>−cos<span>(x)</span></span></span>)</span>′</span>=</span><span><span>=<span><span><span><span>(<span>sin<span>(x)</span>+cos<span>(x)</span></span>)</span>′</span>⋅<span>(<span>sin<span>(x)</span>−cos<span>(x)</span></span>)</span>−<span>(<span>sin<span>(x)</span>+cos<span>(x)</span></span>)</span>⋅<span><span>(<span>sin<span>(x)</span>−cos<span>(x)</span></span>)</span>′/</span></span><span><span>(<span>sin<span>(x)</span>−cos<span>(x)</span></span>)^</span>2</span></span></span>=</span><span>=<span><span><span><span>(<span><span><span>(<span>sin<span>(x)</span></span>)</span>′</span>+<span><span>(<span>cos<span>(x)</span></span>)</span>′</span></span>)</span>⋅<span>(<span>sin<span>(x)</span>−cos<span>(x)</span></span>)</span>−<span>(<span>sin<span>(x)</span>+cos<span>(x)</span></span>)</span></span><span>⋅<span>(<span><span><span>(<span>sin<span>(x)</span></span>)</span>′</span>−<span><span>(<span>cos<span>(x)</span></span>)</span>′</span></span>)/</span></span></span><span><span>(<span>sin<span>(x)</span>−cos<span>(x)</span></span>)^</span>2</span></span>=</span><span>=<span><span><span><span>(<span>cos<span>(x)</span>+<span>(<span>−sin<span>(x)</span></span>)</span></span>)</span>⋅<span>(<span>sin<span>(x)</span>−cos<span>(x)</span></span>)</span>−<span>(<span>sin<span>(x)</span>+cos<span>(x)</span></span>)</span></span><span>⋅<span>(<span>cos<span>(x)</span>−<span>(<span>−sin<span>(x)</span></span>)</span></span>)/</span></span></span><span><span>(<span>sin<span>(x)</span>−cos<span>(x)</span></span>)^</span><span>2</span></span></span></span>
1.Правило "Пифагоровой тройки"
Если гипотенуза 17 , катеты 15 и 8
как если гипотенуза 10, катеты 6 и 8.
2.за 12 часов
<span>в одном метре 100 сентиметров. ! метр в кубе = 1 м*1м*1м=100см*100см*100см=1 000 000 см = 1 миллион сантиметров в кубе</span>
Cos^2a + sin^2a = 1, значит cos^2a = 1-sin^2a = -(sin^2a-1)
-(sin^2a-1) = 0,3, значит sin^2a-1 = -0,3, то есть 5 sin^2a-1 = -1,5
надеюсь, я правильно прочитал условие задачи