math Flashcards
1
Q
roots of f(x) = f-1(x) lie on which line?
A
y = x
2
Q
if two roots of ax2 + bx + c = 0 are in the ratio m:n
A
mnb2 = (m+n)2ac
3
Q
if a1x2 + b1x + c1 =0 and a2x2 + b2x + c2 =0 have a common real root
A
(a1c2 - a2c1)2 = (b1c2 - b2c1)(a1b2 - a2b1)
4
Q
incentre
A
x = (ax1 + bx2 + cx3)/(a + b + c)
5
Q
excentre
A
-ve of incentre
6
Q
area of triangle in terms of a, b, c
A
area = (1/2)ab sinc
7
Q
loga1 = ?
A
0
8
Q
logaa = ?
A
1
9
Q
logamn = ?
A
logam + logan
10
Q
logamn = ?
A
nlogam
11
Q
logabm = ?
A
(1/b)logam
12
Q
logba = ?
A
(logma)/(logmb)
13
Q
alogam = ?
A
m
14
Q
∫axdx
A
ax/ln a + c
15
Q
2 points (x1, y1) and (x2, y2) lie on the same side of straight line ax + by + c = 0 if ?
A
ax1 + by1 + c and ax2 + by2 + c have the same sign