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<p style="font-size:17px;line-height:30px;margin:10px 0px;color:#333333;font-weight:900;" data-flag="subtitle" lang="en">【习题课】6个例题搞懂平面镜成像作图</p><p style="color:#333333;font-weight:normal;font-size:16px;line-height:30px;font-family:Helvetica,Arial,sans-serif;hyphens:auto;text-align:justify;" data-flag="normal" lang="en"><img data-key="0" src="http://imagev2.xmcdn.com/storages/26d6-audiofreehighqps/DD/A4/GMCoOSUIVg6gAAKbigImh8XN.jpg!op_type=4&upload_type=attachment&device_type=ios&name=mobile_large" alt="" data-origin="http://fdfs.xmcdn.com/storages/26d6-audiofreehighqps/DD/A4/GMCoOSUIVg6gAAKbigImh8XN.jpg" data-preview-width="140" data-large="http://imagev2.xmcdn.com/storages/26d6-audiofreehighqps/DD/A4/GMCoOSUIVg6gAAKbigImh8XN.jpg!op_type=4&upload_type=attachment&device_type=ios&name=mobile_large" data-large-height="191" data-preview="http://imagev2.xmcdn.com/storages/26d6-audiofreehighqps/DD/A4/GMCoOSUIVg6gAAKbigImh8XN.jpg!op_type=4&upload_type=attachment&...