Prove that an integer is odd if and only if it is the sum of two consecutive integers.

A proof can be as follows:

Step-by-step explanation:

Remember that an odd interger is of the form where is a integer and remember that two consecutive integer are two numbers of the form

Suppose the is an odd integer.

Then must be an even integer and hence divisible by 2. Then we define

Then we have that

The converse is as follows:

Let an integer, then  are two consecutive integers. Then

is an odd integer.

where is the figure

the largest number of the four options is 1.8 x 10-2

you have it in scientific notation.

1.80 x 10-6   = 0.00000180

1.80 x 10-4   = 0.000180 (bigger, or "less small", than the former one)

so

1.8 x 10-2       = 0.0180. as you see. the "less small", or the biggest one of them all.

as you have negative exponent, it means you are dividing 1.8 by 100 (i.e. moving the dot towards left, two times).

if you had positive exponent for the scientific notation, power of tenths, you would be multiplying times 100 (moving the dot towards right) as below:

1.8 x (10)2 = 180

so. if you have negative exponent in scientific notation, move the dot toward left. if it is positive, toward right as many times the exponent tells you.