The fact that a1 is contained in this means a1 is in the ideal generated by a 2; that means, a 2 times b 2 for some b 2. So, a1 can be written as a 2 b 2, but a 2 is in the ideal generated by a 3 which means we have a 3 b 3 b 2.
तथ्य यह है कि a1 a2 द्वारा जनरेटेड आइडियल में है इसका मतलब है a1 बराबर a2 b2; a2 a3 द्वारा जनरेटेड आइडियल में है, इसका मतलब है कि हमारे पास a3 b3 b2 है।