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If the circle x^2+y^2+2ax+8y+16=0 touche...

If the circle `x^2+y^2+2ax+8y+16=0` touches x axis, then the vlaue of a is:

A

`pm1`

B

`pm4`

C

`pm8`

D

none of these

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JBD PUBLICATION-MODEL PAPER (15)-EXERCISE
  1. The nth term of a G.P. is 128 and the sum of its n terms is 225. If it...

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  2. The three striaght lines ax+by=c, bx+cy=a and cx+ay=b are collinear if...

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  3. If the circle x^2+y^2+2ax+8y+16=0 touches x axis, then the vlaue of a ...

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  4. In a single toss of three coins, the probability of getting head and t...

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  5. Prove that:(sinx +sin3x)/(cosx+cos3x)=tan2x

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  6. Prove that (sin(x+y))/(sin(x-y))=(tanx+tany)/(tanx-tany)

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  7. If z1= 2 -i, z2= 1+ i, find |(z1+z2+1)/(z1-z2+1)|.

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  8. Show that 9^(n+1) - 8n -9 is divisible by 64, whenever n is a positiv...

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  9. Compute (98)^5

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  10. Using distance formula, show that the points A(6,-7,1), B(2,-3,1) and ...

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  11. Show that the statement is true by the method of contradiction. If x i...

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  12. Find the component statement of the following and check whether they a...

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  13. Prove that A^c-B^c=B-A.

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  14. If f(x)=log(x/(x-1)), show that f(x+1)+f(x)=log ((x+1)/(x-1))

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  15. Prove that:cos15^@-sin15^@=1/sqrt2

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  16. Prove that : cos 24^@+ cos 55^@ + cos 125^@ + cos204^@ + cos 300^@= 1/...

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  17. How many words, with or without meaning, each of 2 vowels and 3 conson...

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  18. Find the value of n such that : "^nP5=42 ^nP3, n>4.

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  19. Sum of first p,q and r terms of an A.P. are a,b,c respectively. Prove...

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  20. If the angle between two lines is pi/3 and slope of one of the line is...

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