Reflection on 25th March 2013

Like last week, today we watch some video. In this lecture there are three video, not only video about mathematics but also about motivation. Titles of this video are ‘Quadratic Form’, ‘Invers Function’, and ‘Do You Believe Me?’.

In mathematics quadratic form is a quadratic form over some real vector space V that has the same sign(always positive or always negative) for every nonzero vector of V. According to that sign, the quadratic form is calledpositive definite or negative definite. A semidefinite (or semi-definite) quadratic form is defined in the same way, except that "positive" and "negative" are replaced by "not negative" and "not positive", respectively. An indefinite quadratic form is one that takes on both positive and negative values.

‘Do You Believe Me?’ is a Inspirational video for the start of school video. This video, posted to YouTube and created for the Starkville (Mississippi) School District by Broadcast Media Group,  is a great video to share with teachers, administrators, students, parents, and other constituents in our educational community. This video participants answer the basic and important questions:

1.      What do you want to be when you grow up?

2.      Why did you become a teacher?

3.      Who is your favorite teacher? What is your favorite subject? Why?

An inverse function is a function that undoes another function: If an input x into the function f produces an output y, then putting y into the inverse function g produces the output x, and vice versa. i.e., f(x)=y, andg(y)=x. More directly, g(f(x))=x, meaning g(x) composed with f(x) leaves xunchanged. A function f that has an inverse is called invertible; the inverse function is then uniquely determined by f and is denoted by f⁻¹ (read f inverse, not to be confused with exponentiation).