MEDIUM
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If tangents are drawn from a point P to the parabola y2=4x with focus (S) such that the lengths of the tangents are 5 and 10, then SP is equal to

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Important Questions on Parabola

MEDIUM
Let a, b and c be the 7th, 11th and 13th terms respectively of a non-constant A.P. If these are also the three consecutive terms of a G.P., then ac is equal to:
MEDIUM
If a, b and c be three distinct real numbers in G.P. and a+b+c=xb, then x cannot be:
HARD
Let bi>1 for i=1, 2,.,101. Suppose logeb1,logeb2,..,logeb101 are in Arithmetic Progression (A.P.) with the common difference loge2.  Suppose a1, a2,.,a101 are in A.P. such that a1=b1 and a51=b51. If t=b1+b2++b51 and s=a1+a2++a51, then
MEDIUM
The sum of the 3rd and the 4th terms of a G.P. is 60 and the product of its first three terms is 1000. If the first term of this G.P. is positive, then its 7th term is:
MEDIUM
The focus of the parabola y=2 x 2 +x is
MEDIUM
The sum of first 20 terms of the sequence 0.7, 0.77, 0.777, ......, is :
HARD

If m is the A.M. of two distinct real numbers I and n I, n>1  and G1, G2 and G3 are three geometric means between I and n, then G14+2G24+G34 equals

MEDIUM
The sum of the first 20 terms of the series 1+32+74+158+3116+ is
HARD
If the tangents and normals at the extremities of a focal chord of a parabola intersect at x1,y1 and x2,y2 respectively, then
HARD
Let E denote the parabola y2=8x. Let P=-2,4, and let Q and Q' be two distinct points on E such that the lines PQ and PQ' are tangents to E. Let F be the focus of E. Then which of the following statements is (are) TRUE?
MEDIUM
Three positive numbers form an increasing G.P. If the middle term in this G.P. is doubled, the new numbers are in A.P. Then the common ratio of the G.P. is :
MEDIUM
Let A1,2, B4,-4, C2,22 be points on the parabola y2=4x. If α and β respectively represent the area of ΔABC and the area of the triangle formed by the tangents at A, B, C to the above parabola, then αβ=
MEDIUM
The quotient when 1+x2+x4+...+x34 is divided by 1+x+x2+...+x17 is
HARD
The number of real solutions of the equation sin-1i=1xi+1-xi=1x2i=π2-cos-1i=1 -x2i-i=1-xi lying in the interval -12,12 is____.

(Here, the inverse trigonometric functions sin-1x & cos-1x assume values in -π2,π2 & 0,π

respectively.)
MEDIUM
Suppose p, q, r are real numbers such that q=p4-p, r=q4-q, p=r4-r. The maximum possible value of p+q+r is
MEDIUM
Let f:xy be such that f1=2 and fx+y=fxfy for all natural numbers x and y . If k=1 n f( a+k )=16( 2 n 1 ) then a is equal to
HARD
Let x,y,z be three non-negative integers such that x+y+z=10. The maximum possible value of xyz+xy+yz+zx is
MEDIUM
The sum of the first 10 terms of the series 9+99+999+.. is
EASY
If the three normals drawn to the parabola, y2=2x pass through the point a,0, a0, then a must be greater than :
MEDIUM
Suppose OABC is a rectangle in the xy-plane where O is the origin and A,B lie on the parabola y=x2. Then C must lie on the curve-