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Showing posts from January, 2021

Foot of perpendicular short trick

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 Foot of Perpendicular from a given point on a line Let  P : (x1 ,  y1) be the point and L : (ax + by + c = 0) be the line . Let (x , y) be the foot of perpendicular.  Method 1 : Let  '' m1 ''  be the slope of  line '' L ''. m1 = -a / b Now , we make a line perpendicular to  '' L '' passing through ''  P  ''. So, slope of that line is (-1 / m1) and passing point point is (x1 , y1). We can find line equation by using point slope form. And, then find the intersection point of given line and above line. But this method is time consuming. Method 2 :  Example : Let 2x + y = 3 be the line and (1, 2) be the point . So, L :  2x + y - 3 = 0   { a = 2  ;   b = 1 ;  c = -3} P : (1 ,  2) {x1 = 1 ;  y1  = 2} Now,  x - 1  =  y - 2  =  - 1     2           1           5      x - 1 ...

How to find number of common tangents between two circles ?

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         Finding    common   tangents    b/w    two    circles Q.). What is the meaning of  common tangents ? Ans.)  Its  meaning is as simple as its name, a common tangent is a tangent that is tangent to both the given curves. These curves may be two parabolas , one parabola and a circle or may be hyperbola and a parabola. Actually, there are immense possibility what these curves can be. But we will specifically discuss about two circles in this post. There are maximum " 4 " possible common tangents b/w to circles and minimum is zero. OK lets understand by diagrams. Now, we will discuss how to calculate number of common tangents b/w two circles : Let C1 and C2 be two circles with r1 and r2 be there respective radius and (x1, y1) and (x2, y2) be the centre of C1 and C2 respectively. Let " D " be the distance b/w centre of two circles C1 and C2. Now, If 1)            ...

How to ask NCERT class 12 maths or JEE maths doubts ?

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  If you have any doubt in any question of  NCERT class 12 maths or JEE maths  just take a pic of that question or type that question and just mail at Email - ID  :  Email ID  : jeemathsolutions@gmail.com You can ask any previous year :  1)  JEE maths question  2)  NCERT class 12 maths or 11 maths problems  3) Any previous year CBSE maths problems For any problems related to NCERT class 12 maths or JEE maths feel free to contact us via email ID :    jeemathsolutions@gmail.com  

Got stuck in JEE Maths ?

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Unable to find solution to some difficult Maths problems and has become nightmare(👿) ? No problem because we are here to solve them, just ask and we will provide you most detailed solutions like this :  Q.)A line parallel to the straight line 2x - y = 0 is tangent to hyperbola P at point (x1 , y1). Then x 1 ^2 + 5y 1 ^2 is equal to : a) 6 b) 8 c) 10 d) 5 where P :  Solution:  Let's draw a sketch for hyperbola P and line: Tangent to point (x1, y1) to P is :  x.x1/4 - y.y1/2 = 1 As this is parallel to given line both have same slope. So, x 1 /2y 1 = 2  --->   x 1  = 4y 1                            --------- (1) and also point (x 1 , y 1 ) also satisfy P.  So, x 1 ^2 / 4 - y 1 ^2 / 2 = 1                                --------- (2) From above (1) and (2) : y 1 ^2  =  2/7 As, we ...