Get Free Instant Video Solutions to Any Math Question- Doubtnut (Class 6th-12th upto IIT-JEE LEVEL)
1:45
Get Free Instant Video Solutions to Any Math Question- Doubtnut (Cla…
1.9M viewsApr 14, 2019
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Find the value of `a` and `b` so that the polynomial `x^3-a x^2-13 x+b` has `(x-1)` and `(x+3)` ...
4:38
Find the value of `a` and `b` so that the polynomial `x^3-a x^2-13 x+b` …
15.9K viewsDec 12, 2017
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Using vector method, prove that the following points are collinear: lt br gt A(2,-1,3) B(4,3,1) ...
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Using vector method, prove that the following points are collinear: lt b…
29.2K viewsJun 22, 2018
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If AM and GM of two positive numbers `a\\ a n d\\ b`\nare 10 and 8 respectively, find the numbers.
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If AM and GM of two positive numbers `a\\ a n d\\ b`\nare 10 an…
17.6K viewsJun 22, 2018
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The pair of linear equations `3x+2y=5;2x-3y=7`\nhave\nOne solution (b) Two solution\nMany solution...
3:13
The pair of linear equations `3x+2y=5;2x-3y=7`\nhave\nOne so…
55.8K viewsSep 21, 2017
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Find the equations of the circles touching y-axis at (0,3) and making\r\n an intercept of 8 uni
3:44
Find the equations of the circles touching y-axis at (0,3) and makin…
9.2K viewsJun 22, 2018
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Prove that: `(sin5x-2sin3x+sin x)/(cos5x-cos x)=tanx`
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Find in video from 00:12Initial Solution
Prove that: `(sin5x-2sin3x+sin x)/(cos5x-cos x)=tanx`
52.7K viewsJun 22, 2018
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The sum of four consecutive numbers in A.P. is 32 and the ratio of the product of the first and last
2:09
The sum of four consecutive numbers in A.P. is 32 and the rati…
55.1K viewsMay 4, 2018
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If `x^3-1/(x^3)=14 ,`\nthen `x-1/x=?`\n\n(a)5\n (b) 4 (d) 3\n (d) 2
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If `x^3-1/(x^3)=14 ,`\nthen `x-1/x=?`\n\n(a)5\n (b) 4 (d) 3\n (d) 2
8.8K viewsJun 22, 2018
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Find `(x+1)^6+(x-1)^6`. Hence evaluate `(sqrt(2)+1)^6+(sqrt(2)-1)^6`.
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Find `(x+1)^6+(x-1)^6`. Hence evaluate `(sqrt(2)+1)^6+(sqrt(2)-1)…
8.7K viewsJun 22, 2018
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The sum of first three terms of a G.P. is 13/12 and their product is\r\n -1. Find the G.P.
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The sum of first three terms of a G.P. is 13/12 and their product is\r…
16K viewsJun 22, 2018
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Find the percentage\r\n increase in the area of a triangle if its each side is doubled.
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Find the percentage\r\n increase in the area of a triangle if its each si…
18K viewsJun 22, 2018
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Find the equation of an ellipse whose eccentricity is 2/3, the latus\r\n rectum is 5 and the ce
4:42
Find the equation of an ellipse whose eccentricity is 2/3, the latu…
8.7K viewsJun 22, 2018
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Solve: `x/a+y/b=a+b`\n\n`x/(a^2)+y/(b^2)=2`
3:55
Solve: `x/a+y/b=a+b`\n\n`x/(a^2)+y/(b^2)=2`
26.4K viewsSep 20, 2017
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If 3rd, 4th, 5th terms in the expansion of `(a+x)^n` be 84, 280 and 560, Find x, a and n.
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If 3rd, 4th, 5th terms in the expansion of `(a+x)^n` be 84, 280 …
6.6K viewsSep 14, 2017
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. An equilateral triangle has two vertices at the points `(3, 4)` and `(2, 3)`, find the codrd...
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. An equilateral triangle has two vertices at the points `(3, 4)` and `(…
24.6K viewsJul 30, 2018
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Evaluate `1+i^2+i^4+i^6+...+i^(2n)dot`
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Evaluate `1+i^2+i^4+i^6+...+i^(2n)dot`
6.9K viewsSep 19, 2017
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A train\r\n travels a distance of 480 km at a uniform speed. If the speed had been 8\r\n km/hr l
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A train\r\n travels a distance of 480 km at a uniform speed. If the spee…
159.9K viewsJun 22, 2018
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If `cos theta=-1/2` and `0^@ lt theta lt 360^@` then the solutions are `a. 60^@, 240^@, b.12
1:55
If `cos theta=-1/2` and `0^@ lt theta lt 360^@` then the solutions are `a…
16.3K viewsJun 22, 2018
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If `25^(n-1) + 100 = 5 (2n-1)`, find the value of n :
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If `25^(n-1) + 100 = 5 (2n-1)`, find the value of n :
38.9K viewsJul 30, 2018
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If `y=sqrt(x/a)+sqrt(a/x)` , prove that `2x y(dy)/(dx)=(x/a-a/x)`
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If `y=sqrt(x/a)+sqrt(a/x)` , prove that `2x y(dy)/(dx)=(x/a-a/x)`
7.4K viewsSep 19, 2017
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Prove that: `tan^(-1){(sqrt(1+x)-sqrt(1-x))/(sqrt(1+x)+sqrt(1-x))}=pi/4-1/2\\\\ cos^(-1)x ,\\\\ \\\\ 0...
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Prove that: `tan^(-1){(sqrt(1+x)-sqrt(1-x))/(sqrt(1+x)+sqrt(1-x))}=pi/…
15.7K viewsJun 22, 2018
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Prove that measure of each angle of an equilateral triangle is `60^0dot`
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Prove that measure of each angle of an equilateral triangle is `60^0dot`
26.1K viewsSep 20, 2017
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Prove that:\n`1/(1+x^(b-a)+\\ x^(c-a))+1/(1+x^(a-b)+\\ x^(c-b))+1/(1+x^(b-c)+x^(a-c))=1`
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Prove that:\n`1/(1+x^(b-a)+\\ x^(c-a))+1/(1+x^(a-b)+\\ x^(c-b))+1/(1+x…
26.4K viewsJun 22, 2018
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Find the equation of the circle with: centre (-2,3) and radius 4.
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Find the equation of the circle with: centre (-2,3) and radius 4.
11.8K viewsJun 22, 2018
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Points `(-4,\\ 0)a n d\\ (7,\\ 0)` lie\n(a) on x-axis\n(b) on y-axis\n(c) in first quadrant\n(d) In s
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Points `(-4,\\ 0)a n d\\ (7,\\ 0)` lie\n(a) on x-axis\n(b) on y-axis\n(c) in firs…
4.8K viewsJun 22, 2018
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Without actual division prove that `2x^4- 6x^3 +3x^2+3x-2` is exactly divisible by `x^2- 3x +2`...
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Without actual division prove that `2x^4- 6x^3 +3x^2+3x-2` is exactl…
13.3K viewsJul 30, 2018
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Show graphically that the system of equations\n`2x+4y=10`\n\n`3x+6y=12`
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Show graphically that the system of equations\n`2x+4y=10`\n\n`3x+6y=…
6.7K viewsSep 20, 2017
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The sum and product of two complex numbers are real if and only if they are conjugate of each ot...
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The sum and product of two complex numbers are real if and o…
9.9K viewsSep 19, 2017
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How many three-digit numbers more than 600 can be formed by using the digits 2, 3, 4, 6, 7.
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Find in video from 00:27Solution Approach
How many three-digit numbers more than 600 can be formed by u…
8.2K viewsSep 19, 2017
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