Ignore tht pascal triangle its way too inefficient
Formula nCr = n! /r! (n-r)!
So 6C3= 6!/3!(6-3)!=20
Answer:
Required coefficient :coefficient of 1st, 2nd, 3rd and 4th term are 1, 3,3,1 respectively.
Explanation:
Formula for binomial expansion is 
We will substitute the values a=a, b=b and n=3 in the formula for binomial expansion we will get

After simplification of the terms we will get

Since, 
Therefore the required coefficient : coefficients of 1st, 2nd, 3rd and 4th term are 1, 3,3,1 respectively.
Answer:
For a function y = f(x), the range is the set of all the possible values of y.
In the question you wrote:
y = secx - 2
This can be interpreted as:
y = sec(x - 2)
or
y = sec(x) - 2
So let's see each case (these are kinda the same)
If the function is:
y = sec(x - 2)
Firs remember that:
sec(x) = 1/cos(x)
then we can rewrite:
y = 1/cos(x - 2)
notice that the function cos(x) has the range -1 ≤ y ≤ 1
Then for the two extremes we have:
y = 1/1 = 1
y = 1/-1 = -1
Notice that for:
y = 1/cos(x - 2)
y can never be in the range -1 < x < 1
As the denominator cant be larger, in absolute value, than 1.
Then we can conclude that the range is all reals except the interval:
-1 < y < 1
If instead the function was:
y = sec(x) - 2
y = 1/cos(x) - 2
Then with the same reasoning, the range will be the set of all real values except:
-1 - 2 < y < 1 - 2
-3 < y < -1
A is the correct answer. Hope this helps. I need brainliest so if you can I really appreciate it!
Answer:
The number 1.256 is A)rational number.
Step-by-step explanation:
- A whole number is a non-negative number without any digits behind the decimal.
- An integer is a set of negative and non negative numbers that don't have any digits behind the decimal.
- A number that can be shown as a fraction of two whole numbers is a rational number.And the numbers that are not rational are irrational numbers.
- Here, 1.256 is a fraction of whole numbers 1256 and 1000 , so it is a rational no.

- But since it has digits behind the decimal it is neither a whole number, or an integer.