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błagam o pomoc:) eheheh: Stosunek pola powierzchni bocznej stożka do jego pola podstawy jest równy 2 : 1. Objetosc stozka jest rowna objętości kuli o średnicy 6. Oblicz wysokość tego stożka.
8 sty 15:10
Janek191: Pb = π r l Pp = π r2 Pb / Pp = 2 / 1 π r l 2 −−−− = −−−− π r2 1 zatem l / r = 2 l = 2 r => l2 = 2 r2 −−−−−−−−−− Z tw. Pitagorasa mamy l2 = r2 + h2 2 r2 = r2 + h2 r2 = h2 r = h ==== Vs = Vk więc (1/3) π r2 * h= (4/3) π R3 / *( 3/π) ; gdzie 2 R = 6 => R = 3 r2 *h = 4 R3 = 4* 33 h3 = 4*27 = 108 h = 3108 = 327*4 = 334 Odp. h = 334 =================
8 sty 17:07
Janek191: Pb = π r l Pp = π r2 Pb / Pp = 2 / 1 π r l 2 −−−− = −−−− π r2 1 zatem l / r = 2 l = 2 r => l2 = 2 r2 −−−−−−−−−− Z tw. Pitagorasa mamy l2 = r2 + h2 2 r2 = r2 + h2 r2 = h2 r = h ==== Vs = Vk więc (1/3) π r2 * h= (4/3) π R3 / *( 3/π) ; gdzie 2 R = 6 => R = 3 r2 *h = 4 R3 = 4* 33 h3 = 4*27 = 108 h = 3108 = 327*4 = 334 Odp. h = 334 =================
8 sty 17:08