Harry - a vivd reader of askalwayslovely.blogspot.com sent me an email asking about solving of the following question. He did it using trial and error. I believe it will take him some time. He felt that his approach was not the best so he emailed me asking for alternatives.
In fact for this question, there is a step by step way which will get us the answer in less than 8 minutes time.
Question: If the coefficient of [pmath]x^k[/pmath] and [pmath]x^(k+1)[/pmath] in the expansion of [pmath](2x+3)^19[/pmath] are equal, find [pmath]k[/pmath]
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Ai Ling Ong
Hi, I'm Ai Ling Ong. I enjoy coaching students who have challenges with understanding and scoring in 'O' Level A-Maths and E-Maths. I develop Math strategies, sometimes ridiculous ideas to help students in understanding abstract concepts the fast and memorable way. I write this blog to share with you the stuff I teach in my class, the common mistakes my students made, the 'way' to think, analyze... If you have found this blog post useful, please share it with your friends. I will really appreciate it! :)
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