第四章一次函数全章教案

\ry = ----- 1 + ------ ,‡ y=0',\r3 3\r`3 X + ¶ = 0 } x=4,\r...Ž E (4, 0)o\r3 3\r( 2 ) :¸ ¹ AEF 5¡º AE=2AF, A ZAEF=30° , V ZAOE=60° ,.\r/.ZAEF=90° o /.0A±AE\r20. z (1) Š.Š+2296m/min@P`p?\r??\r+22¿+'*.eÀ & =25 (min),™ 0F=25,\r96\rÂ4e S2( t )*+GHIJP.eS2=kt+b,\rV E (0, 2400), F (25, 0),\rb = 2400 “ E b = 2400\rz}e\r25k + b = Q A: =-96\rQ.S2( t )*+GHIJP.es2= - 96t+2400Q\r( 2 ) Â4e¿Æ 1 0 @ÇÈp?,\r.ŠŠDŽ+ÉÊ.(22, 0),\r°7B D ™ si( t )*+GHIJP.esi=at+c+\r12a + c = 2400\r224 + c = 0\ra = -240\rz}:\rc = 5280\r, ( t )*+GHIJP.:s,= - 240t+5280,\r‡ s ÍS2'W5XY22,\r™ - 96t+2400= - 240t+5280,\rz}et=20,\rSI=S2=480,\r.ŠŠ`!"#$20minÎ|W5XY22[' ,-\r\]480m.