Maths

Get insights from 6.5k questions on Maths, answered by students, alumni, and experts. You may also ask and answer any question you like about Maths

Follow Ask Question
6.5k

Questions

0

Discussions

18

Active Users

0

Followers

New answer posted

a year ago

0 Follower 5 Views

P
Payal Gupta

Contributor-Level 10

L 1 : x − 3 2 = y − 2 3 = z − 1 − 1  

L 2 : x + 3 2 = y − 6 1 = z − 5 3               

Now,

p → * q → = | i ^ j ^ k ^ 2 3 − 1 2 1 3 | = 1 0 i ^ − 8 j ^ − 4 k ^               

and

  a → 2 − a → 1 = 6 i ^ − 4 j ^ − 4 k ^

  ∴ S . D = | 6 0 + 3 2 + 1 6 1 0 0 + 6 4 + 1 6 | = 1 0 8 1 8 0 = 1 8 5      

New answer posted

a year ago

0 Follower 3 Views

P
Payal Gupta

Contributor-Level 10

L 1 : x − 3 2 = y − 2 3 = z − 1 − 1  

L 2 : x + 3 2 = y − 6 1 = z − 5 3               

Now,

p → * q → = | i ^ j ^ k ^ 2 3 − 1 2 1 3 | = 1 0 i ^ − 8 j ^ − 4 k ^               

and

  a → 2 − a → 1 = 6 i ^ − 4 j ^ − 4 k ^

  ∴ S . D = | 6 0 + 3 2 + 1 6 1 0 0 + 6 4 + 1 6 | = 1 0 8 1 8 0 = 1 8 5                           

New answer posted

a year ago

0 Follower 17 Views

P
Payal Gupta

Contributor-Level 10

C : 4x2 + 4y2 – 12x + 8y + k = 0

? ( 1 , − 1 3 )               

Lies on or inside the C then

4 + 4 9 − 1 2 − 8 3 + k ≤ 0

⇒ k ≤ 9 2 9               

Now, circle lies in 4th quadrant centre

≡ ( 3 2 , − 1 )               

∴ r < 1 ⇒ 9 4 + 1 − k 4 < 1               

⇒ 1 3 4 − k 4 < 1

⇒ k 4 > 9 4

⇒ k > 9

∴ K ∈ ( 9 , 9 2 9 )      

New answer posted

a year ago

0 Follower 51 Views

P
Payal Gupta

Contributor-Level 10

Given vertex is  (5, 4) and directrix 3x + y – 29 = 0

Let foot of perpendicular of (5, 4) on directrix be (x1, y1)

x 1 − 5 3 = y 1 − 4 1 = − ( − 1 0 ) 1 0               

∴ ( x 1 , y 1 ) = ( 8 , 5 )               

So, focus of parabola will be S = (2, 3)

Let P(x, y) be any point on parabola, then

⇒ ( x − 2 ) 2 + ( y − 3 ) 2 = ( 3 x + y − 2 9 ) 2 1 0               

⇒ x 2 + 9 y 2 − 6 x y + 1 3 4 x − 2 y − 7 1 1 = 0               

And given parabola

x 2 + a y 2 + b x y + c x + d y + k = 0               

∴ a = 9 , b = − 6 , c = 1 3 4 , d = − 2 , k = − 7 1 1               

∴ a + b + c + d + k = 5 7 6    

New answer posted

a year ago

0 Follower 8 Views

P
Payal Gupta

Contributor-Level 10

(tan−1y)−x)dy=(1+y2)dx

dxdy+x1+y2=tan−1y1+y2

l.F=e∫11+y2dy=etan−1y

x.etan−1y∫etan−1ytan−1y1+y2dy

Let

etan−1y=t

=xetan−1y=etan−1yy−etan−1y+c...(i)

? It passes through (1, 0) = c = 2

Now put y = tan 1, then

ex = e – e + 2

⇒x=26

New answer posted

a year ago

0 Follower 6 Views

P
Payal Gupta

Contributor-Level 10

∫0117(1x)dx,let1x=t

−1x2dx=dt

=∫∞11−t27|t|dt=∫1∞1t27|t|dt

=17[−1t]12+172[−1t]23+173[−1t]23+...

=∑n=1∞17n(1n−1n+1)

=1+6log67

New answer posted

a year ago

0 Follower 4 Views

P
Payal Gupta

Contributor-Level 10

∫cosx1t2f (t)dt=sin3x+cosx

⇒sinxcos2xf (cosx)=3sin2xcosx−sinx

⇒f' (cosx) (−sinx)=3sec2x−2sec2tanx

cosx=13

∴f' (13) (−23)=9−62

13f' (13)=6−9

New answer posted

a year ago

0 Follower 6 Views

P
Payal Gupta

Contributor-Level 10

f (x)=∫0x2t2−5t+42+etdt

f' (x)=2x (x4−5x2+42+ex2)=0

x=0, or   (x2−4) (x2−1)=0

x=0, x=±2, ±1

Now,

f' (x)=2x (x+1) (x−1) (x+2) (x−2)ex2+2

Changes sign from positive to negative at x = 1, 1 So, number of local maximum points = 2

Changes sign from negative to positive at

x = 2, 0, 2 So, number of local minimum points = 3

∴m=2, n=3

New question posted

a year ago

0 Follower 3 Views

New answer posted

a year ago

0 Follower 7 Views

P
Payal Gupta

Contributor-Level 10

This is a short answer type question as classified in NCERT Exemplar

Given   points are  A(2,3,4),  B(−1,2,−3)  and  C(−4,1,−10)        AB=(2+1)2+(3−2)2+(4+3)2=9+1+49=59        BC=(−1+4)2+(2−1)2+(−3+10)2=9+1+49=59        AC=(2+4)2+(3−1)2+(4+10)2=36+4+196=236=259∴    AB+BC=AC    59+59=259Hence,  A,B  and  C  are  collinear  and  AC:BC=259:59=2:1Hence,  C  divides  AB  is  2:1  externally.

Get authentic answers from experts, students and alumni that you won't find anywhere else

Sign Up on Shiksha

On Shiksha, get access to

  • 67k Colleges
  • 1.2k Exams
  • 718k Reviews
  • 1850k Answers

Share Your College Life Experience

×
×

This website uses Cookies and related technologies for the site to function correctly and securely, improve & personalise your browsing experience, analyse traffic, and support our marketing efforts and serve the Core Purpose. By continuing to browse the site, you agree to Privacy Policy and Cookie Policy.