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How many 4 letter word can formed using the letter of the word of ineffective

Posted by Rohit Kumar 6 years, 11 months ago

CBSE > Class 11 > Mathematics

1 answers

Gaurav Seth 6 years, 11 months ago

There are 11 letters in the word INEFFECTIVE i.e E E E, F F, I I, C, T, N, V=6c1

(i) There is only one set of three same letters i.e E E E.These 4 letter can be arranged in ways=4!/3!1!

Hence the total number of words consisting of 3 same and one different letters = 6c1×4!
6×4=24.

(ii) There are three sets of two some letters i.e E E, F F, I I . Out of these three sets two can be selected in ways.Now, 4 letters in each group can be arranged in ways.=3c2

Hence the total number of words consisting two same letters of one kind and 2 same letters of other kind =3c2×4!/2!2!
=3×6=18

(iii) Out of 3 sets of two same letters one set can be chosen in ways.Now, from the remaining 6 distinct letters, 2 letters can be chosen in ways. So there are group of 4 letters each

=3c1×6c2

Now, letters of each group can be arranged among themselves in ways. = 4!/2!

Hence, the total number of words consisting two same letters and 2 different = (3c1×6c2)×4!/2!
=3×15×6=270

(iv) There are 7 distinct letters E, F.So the total number of 4 letters words in which all letters are different = 7c4×4!
=840

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ANSWER

How many three digit numbers are divisible by 7?

Posted by Parvez Alam 6 years, 11 months ago

CBSE > Class 11 > Mathematics

2 answers

Mohit Saini 6 years, 11 months ago

Digit divided by 7=105,112,119..........,994 it is in A.P USING An=a+(n-1)d, 105+(n-1)7=994 105+7n-7=994 7n=994-98 , 7n=896 , n=896/7=128 So,n=128

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Rohit Gurav 6 years, 11 months ago

Smallest three digit no. divisible by 7 = 105 Largest three digit no. divisible by 7=994 Therefore AP: 105,112,119,....,994. Using nth term formula, an=a+(n-1)d We get n = 128. Ans. 128 three digit numbers are divisible by 7

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Prove that sinx + cos x=1

Posted by Sonu Riar 6 years, 11 months ago

CBSE > Class 11 > Mathematics

1 answers

Sinchana Malagond 6 years, 11 months ago

sin x + cos x is equal to 1 so on squaring both sides science sin x sin square x is equal to 1 - cos x cos square sin square x is equal to 1 - 2 cos x + cos square x so on both on lhs and RHS one gets cancelled then 2 cos x - 2 cos square x is equal to zero let us consider f of x is equal to 2 cos x - 2 cos square x so on common to cos x bracket 1 - cos x is equal to zero cos x is equal to zero cos x is equal to -1 integrating with potential solutions x is equal to zero x is equal to 5 by 2 x is equal to 3 pi by 2 and x is equal to 25 but only x is equal to zero x is equal to 25 by 2 and X is 2 Pi it is in the period of coordinates zero to buy a real so cos x + sin x is equal to 1

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If sinx=-4/5 and x lies in third quadrant then find the value of cosx/2

Posted by Gur Preet 6 years, 11 months ago

CBSE > Class 11 > Mathematics

0 answers

ANSWER

Solution of 201 and 2017 year paper

Posted by Peeyush Pandey 6 years, 11 months ago

CBSE > Class 11 > Mathematics

0 answers

ANSWER

Find the equation of the circle passing through the point (6, 1) and having is centre on the mid point of the line segment joining the centres of the circle (X-2)^2 +(Y-4)^2 = 65 and (X- 4)^2 + (Y-6)^2=64?

Posted by Ayush Diwakar 6 years, 11 months ago

CBSE > Class 11 > Mathematics

0 answers

ANSWER

how many hours are sufficient for revising sequences and series?

Posted by Known Un 6 years, 11 months ago

CBSE > Class 11 > Mathematics

1 answers

Mohit Singh 6 years, 11 months ago

If you were perfect in solving questions before then one or one and half hour if not then two or two and half hour

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Cos4x=cos2x

Posted by Prince Ahlawat 5 years, 9 months ago

CBSE > Class 11 > Mathematics

3 answers

Rashida Khan 6 years, 11 months ago

Ohh sorry cos A - cosB

0Thank You

Rashida Khan 6 years, 11 months ago

Cos(A) +Cos(B) formula

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Abhishek Kumar 6 years, 11 months ago

Cos4x-cos2x=0 Apply cos(A)+cos(B) (formula)

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Find the n if n-1p3:np4=1:9

Posted by Gagandeep Singh 6 years, 11 months ago

CBSE > Class 11 > Mathematics

1 answers

Himanshu Kumar 6 years, 11 months ago

To use parmotation formula and compare n-1p3 to np4 and 1to9

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ANSWER

i+√i

Posted by Awadhesh Kumar Sharma 6 years, 11 months ago

CBSE > Class 11 > Mathematics

0 answers

ANSWER

How many question from each chapter mark wise

Posted by Mohan Kumar 6 years, 11 months ago

CBSE > Class 11 > Mathematics

1 answers

Sanidhya Jadaun? 6 years, 11 months ago

Ch1(6 marks)... Ch2(8 marks)... Ch3(15 marks)... ch4(6 marks)... Ch5(5 marks)... Ch6(6 marks)... Ch7(6 marks)... Ch8(6 marks)... Ch9(8 marks)... Ch10(6 marks)... Ch11(6 marks)... Ch12(2 marks)... Ch13(6 marks)... Ch14(3 marks)... Ch15(6 marks)... Ch16(5 marks)...

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Find the square root of z = -2-2√(3i) ?

Posted by Rohit Kumar 6 years, 11 months ago

CBSE > Class 11 > Mathematics

2 answers

David Th 6 years, 11 months ago

See 474 page no of ncert book class 11example 12 buddy

3Thank You

David Th 6 years, 11 months ago

=-O

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1sin2

Posted by Rajpal Kalra 6 years, 11 months ago

CBSE > Class 11 > Mathematics

0 answers

ANSWER

Prove 7^2n+2^3n-3 3^n-1 is divisible by 5 by binomial expression

Posted by Aanchal Jain 6 years, 11 months ago

CBSE > Class 11 > Mathematics

0 answers

ANSWER

HCF of 196&38220

Posted by Pooja Solanki 6 years, 11 months ago

CBSE > Class 11 > Mathematics

1 answers

Shivshant Prasad 6 years, 11 months ago

hcf means highest common factors which terms occurs common in given terms like 54 and 27 the HCFof them r 54 =2×27 =2×3×3×3 and in 27 = 3×3×3 there u can see 3 is coming three times and is common between both the terms therefore thier hcf is 3×3×3 =27 in ur case the answer is 196 =2×2×7×7 and 38220 = 2×2×3×5×7×7×13 their gcf is 2 ×2×7×7 =196 becoz these numbers r common in both and after multiply their answer is 196

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If tan b=sina-cosa/sina+cosa PT sina+cosa=√2 cosb

Posted by Shubhra Jeet 6 years, 11 months ago

CBSE > Class 11 > Mathematics

0 answers

ANSWER

In how many way we can arrange the letters of word commerce

Posted by Anish Chauhan 6 years, 11 months ago

CBSE > Class 11 > Mathematics

4 answers

Mohit Saini 6 years, 11 months ago

8!/2!2!2!=5040

0Thank You

Shivshant Prasad 6 years, 11 months ago

saif is right here becoz we have 8 alphabet here and three alphabet r repeating these r m,e,c there we divided 8!/2!2!2!

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Gurtaj Singh 6 years, 11 months ago

8!/2!.2!

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Saif Imam 6 years, 11 months ago

8!/2!2!2! = 5040

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Which are the calculus chapter ??

Posted by Abhi Lama 6 years, 11 months ago

CBSE > Class 11 > Mathematics

3 answers

David Th 6 years, 11 months ago

In standard of class or +1 or +2 limits with derivatives are calcus

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Anisha Sharma 6 years, 11 months ago

Integration and limit

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Muskan Khan 6 years, 11 months ago

Integration and differentiation are collective called calculus.

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For all n>1,prove that 1^2+2^2+3^3+....+n^2=n(n+1)(2n+1)/6

Posted by Ishvar Chawda 5 years, 9 months ago

CBSE > Class 11 > Mathematics

1 answers

Manika Gupta 6 years, 11 months ago

First prove for 2 . Put n = 2 and prove LHS and RHS equal then assume the result true for n = k and then prove for n = k + 1 . You get your LHS and RHS equal

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Find slope of line 3x+4y=7

Posted by Panchal Sujal 6 years, 11 months ago

CBSE > Class 11 > Mathematics