<u>Hint </u><u>:</u><u>-</u>
- Break the given sequence into two parts .
- Notice the terms at gap of one term beginning from the first term .They are like
. Next term is obtained by multiplying half to the previous term . - Notice the terms beginning from 2nd term ,
. Next term is obtained by adding 3 to the previous term .
<u>Solution</u><u> </u><u>:</u><u>-</u><u> </u>
We need to find out the sum of 50 terms of the given sequence . After splitting the given sequence ,
.
We can see that this is in <u>Geometric</u><u> </u><u>Progression </u> where 1/2 is the common ratio . Calculating the sum of 25 terms , we have ,
Notice the term
will be too small , so we can neglect it and take its approximation as 0 .

Now the second sequence is in Arithmetic Progression , with common difference = 3 .
![\implies S_2=\dfrac{n}{2}[2a + (n-1)d]](https://tex.z-dn.net/?f=%5Cimplies%20S_2%3D%5Cdfrac%7Bn%7D%7B2%7D%5B2a%20%2B%20%28n-1%29d%5D%20)
Substitute ,
![\implies S_2=\dfrac{25}{2}[2(4) + (25-1)3] =\boxed{ 908}](https://tex.z-dn.net/?f=%5Cimplies%20S_2%3D%5Cdfrac%7B25%7D%7B2%7D%5B2%284%29%20%2B%20%2825-1%293%5D%20%3D%5Cboxed%7B%20908%7D%20)
Hence sum = 908 + 1 = 909
Perimeter = 2L + 2W
since it’s a square, all sides are equal so
perimeter = 4s
s = 13
so multiply 13 by 4
perimeter = 13*4 = 52
Answer:
Explanation given below.
Step-by-step explanation:
The first step is to put the parabola in the form
, which is the <em>standard form of a parabola</em>
<em />
<u>Note:</u> a is the coefficient before x^2 term, b is the coefficient before x term, and c is the independent constant term
The axis of symmetry divides the parabola symmetrically. The axis of symmetry has the equation 
Where <em><u>a and b are the respective values shown above</u></em>
<em><u /></em>
So, that is how you get the axis of symmetry of any parabola.
Answer: the two trains will meet in 2.8 hours
Step-by-step explanation:
Step 1
Speed of train A = 90mph
Speed of train B = 110 mph
Since both trains are travelling towards each other
, their effective speed will be= 90 mph + 110mph= 200mph
Step 2
we know that Speed = distance / time
therefore Time = Distance / speed
Distance = 560 miles
Speed = 200 mph
Time = 560miles / 200mph
2.8 hours