A mathematical moron is given the values b, c, A for a triangle ABC and is required to find the value of a. He does this by using the cosine rule
a2 = b2 + c2 - 2bc.cosA
and misapplying the law of logarithms to this to get
log(a2) = log(b2) + log(c2) - log(2bc.cosA).
He proceeds to evaluate the right-hand side correctly, takes the anti-logarithms and gets the correct answer. What can be said about the triangle ABC?
[ Irish MO 1988 Paper 1 Question 4]
The wording is genuine :-)
If you enjoy using this website then please consider making a donation - every little helps :-)
You can receive these questions directly to your email box or read them in an RSS reader. Subscribe using the links on the right.
Don’t forget to follow Gifted Mathematics on Google+, Facebook or Twitter. You may add your own interesting questions on our Google+ Community and Facebook..
You can also subscribe to our Bookmarks on StumbleUpon and Pinterest. Many resources never make it onto the pages of Gifted Mathematics but are stored in these bookmarking websites to share with you.