In its Fifth Assessment Report, the Intergovernmental Panel on Climate Change, a group of 1,300 independent scientific experts from countries all over the world under the auspices of the United Nations, concluded there's a more than 95 percent probability that human activities over the past 50 years have warmed our planet.
Scalar multiplication of two vectors (to give the so-called dot product) is commutative (i.e., aÂ·b = bÂ·a), but vector multiplication (to give the cross product) is not (i.e., a Ã b = âb Ã a). The commutative law does not necessarily hold for multiplication of conditionally convergent series.
Any operation â for which aâb = bâa for all values of a and b. Addition and multiplication are both commutative. Subtraction, division, and composition of functions are not. For example, 5 + 6 = 6 + 5 but 5 â 6 â  6 â 5. More: Commutativity isn't just a property of an operation alone. It's actually a property of an operation over a particular set. For example, when we say addition is commutative over the set of real numbers, we mean that a + b = b + a for all real numbers a and b. Subtraction is not commutative over real numbers since we can't say that a â b = b â a for all real numbers a and b. Even though a â b = b â a whenever a and b are the same, that still doesn't make subtraction commutative over the set of all real numbers.