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Simranpreet Singh
Subject: Maths
, asked on 14/3/17
Experts and frndss...im so happy I can't explain..earlier 70/70 marks in phy...and now...I got 100/100 marks in maths...omg...im so cheerful ..this is because of ur quick and continuous responses...thnku experts..now bless me to score better in my CBSE class 12.
Answer
1
Aditi Sharma
Subject: Maths
, asked on 8/3/17
1+2+3+......n?1/8(2n+1)^2
Answer
1
Aditi Sharma
Subject: Maths
, asked on 8/3/17
Solve this:
Answer
1
Aditi Sharma
Subject: Maths
, asked on 8/3/17
Solve this:
Answer
1
Simranpreet Singh
Subject: Maths
, asked on 7/3/17
Prove by PMI that :- 1 × 1! + 2×2! + 3×3! + ... + n × n! = (n+1)! - 1
Answer
1
Simranpreet Singh
Subject: Maths
, asked on 7/3/17
In this question..P.T (1+x)
n
>= (1+nx) [for x > -1]...in answer, for n=1...it came.. (1+x) >= (1+x)....so how it's true?....recently I asked a question that whether 0>=0..and the expert said that it's flase...so how this statement is true...clear my doubt..
Answer
1
Abinanth.t
Subject: Maths
, asked on 5/3/17
A box contains 6 red marbles, 5 blue marbles and 4 green marbles. 3 balls are drawn from the box, What is the probability that
(a) All will be blue?
(b) At least one will be green?
Answer
1
Chaitanya Sharma
Subject: Maths
, asked on 28/2/17
12. Find value of
sin
x
2
,
cos
x
2
and
tan
x
2
, given that
sin
x
-
3
4
,
x
∈
I
I
I
quadrant.
13. Prove that
tan
5
x
+
tan
3
x
tan
5
x
-
tan
3
x
=
4
cos
2
x
cos
4
x
Answer
0
Chaitanya Sharma
Subject: Maths
, asked on 28/2/17
Find the equ. of a line perpendicular to x - 2y + 3 = 0 and passing through the points (1,-2)
If A.M and G.M of roots of quad. equ are 8 and 5 resp. then obtain the quad. equ.
If aand b are distint integers, prove that a-b is a factor of
a
n
-
b
n
, whenever n is a +ive integers.
Find the equ. of the circle concentric with the circle
2
x
2
+
2
y
2
+
8
x
+
10
y
-
39
=
0
with radius eaual to 4
Find the coordiantes of focii, vertices, eccntricity, length of latus ractum, length of transerversal axis and conjugate axis of hyperbola
y
2
16
-
x
2
20
=
1
Find the value of Sin x/2 , cos x/2, and tan x/2, givent hat sinx = -3/4, x
∈
III quadrant
Prove that
tan
5
x
+
tan
3
x
tan
5
x
-
tan
3
x
= 4cos2x cos4x
Answer
0
Chaitanya Sharma
Subject: Maths
, asked on 27/2/17
Please solve this all question
Fast
Answer
4
Shubhrajyoti Ghosh
Subject: Maths
, asked on 9/2/17
If
n
belongs to
natural number,
then by
PMI
prove that,
n.1 + (n-1).2 + (n-2).3 + ... + 2.(n-1) + 1.n = n(n+1)(n+2)/6
NO
LINKS PLEASE
Answer
1
Shubhrajyoti Ghosh
Subject: Maths
, asked on 9/2/17
If
n
belong
to
Natural numbers,
then by
PMI prove
that,
(i) 1 + 2 + 3 + g + n < (2n + 1)
2
/8
(ii) 1
2
+ 2
2
+3
2
+ g + n
2
> n
3
/3
NO LINKS PLEASE
Answer
1
Shubhrajyoti Ghosh
Subject: Maths
, asked on 9/2/17
For what natural number
n
the inequality
2
n
> 2n+1
is valid.
[Answer :
n is greater than equal to 3
]
NO LINKS PLEASE
Answer
1
Shubhrajyoti Ghosh
Subject: Maths
, asked on 31/1/17
Prove by Principle of Mathematical Induction that
:
(a)
for every integer,
|sin(nx)|≤n|sinx|
(b)
2
2^n
+1
has 7 in unit's place for all n>=2
(c)
(a
n
+b
n
)
is divisible by (a+b) when n is an odd positive integer.
[
DO NOT CONSIDER
(a),
(b)
AND
(c)
AS TWO SEPARATE QUESTIONS. THIS IS ONE SINGLE QUESTION.]
PLEASE DO NOT GIVE ANY LINK.
THANK YOU
Answer
0
Shubhrajyoti Ghosh
Subject: Maths
, asked on 31/1/17
If
n belongs to N
, then by
PMI
prove that,
(a) n < 2n
(b) 3n > n
3
[n>=4]
(c) 2
n
< n! [n>=4]
(d)3
n
> 2
n
All the above four sub-questions are included in a single question.
Please do not consider them as different questions.
NO LINKS PLEASE
Answer
1
Prev
4
5
6
7
8
Next
What are you looking for?
(a) All will be blue?
(b) At least one will be green?
13. Prove that
Fast
n.1 + (n-1).2 + (n-2).3 + ... + 2.(n-1) + 1.n = n(n+1)(n+2)/6
NO LINKS PLEASE
(i) 1 + 2 + 3 + g + n < (2n + 1)2/8
(ii) 12 + 22 +32 + g + n2 > n3 /3
NO LINKS PLEASE
[Answer : n is greater than equal to 3 ]
NO LINKS PLEASE
(a) for every integer, |sin(nx)|≤n|sinx|
(b) 22^n +1 has 7 in unit's place for all n>=2
(c) (an+bn) is divisible by (a+b) when n is an odd positive integer.
[DO NOT CONSIDER (a), (b) AND (c) AS TWO SEPARATE QUESTIONS. THIS IS ONE SINGLE QUESTION.]
PLEASE DO NOT GIVE ANY LINK.
THANK YOU
(a) n < 2n
(b) 3n > n3 [n>=4]
(c) 2n < n! [n>=4]
(d)3n > 2n
All the above four sub-questions are included in a single question. Please do not consider them as different questions.
NO LINKS PLEASE