# Algebra : Important Formulae & Frequently Asked Questions

Every year 8 to 10 questions are asked from algebra in SSC CGL tier 2.Some aspirants find algebra difficult and for some it’s very easy. It isn’t difficult, but it is unfamiliar. Anyone can score good marks in algebra by following three step preparation :

1. Learn the formulae
2. Practice questions
3. Take some mock tests

We are sharing important formulae which will be very useful in exam. And in section 2 we are sharing some important questions which cover important concepts. By solving each question your basics will be cleared. And in the last section you can find the answers. First solve all the questions then check your answers with the answers given.

Section 1: Algebra Important Formulae

• a2+1a2=a+1a2-2

=a-1a2+2

• a3+1a3=a+1a3-3a+1a

• a3-1a3=a-1a3+3a-1a

• a3+b3+c3-3abc=(a+b+c)(a2+b2+c2-ab-bc-ca)

If a + b + c=0, then  a3+b3+c3=3abc

• If x-a2+y-b2+z-c2=0

Then x=a , y=b, z =c

• If x+1x= -2

Then solve using x= -1

For eg. x32+1x47=-132+-147=1-1=0

• If x+1x=1     and sum is given with powers of x having difference of 3 then its sum will be zero

For eg. x6+x3=0

Section 2 : Frequently Asked Questions

Q1. If  x+1x=1  then find out the value of   x5+1x5

Q2. If   a2+1a2=98  then find out the value of   a3+1a3

Q3. If x= 1+ 2+ 3    then find out the value of   2x4-8x3-5x2+26x-28

Q4. p + 1/p =5 then find out the value of     p4+1p2   p3-3p+1

Q 5. If 5a + 13a=5    then find out the value of  9a2+125a2

Q6.  If a = 2+ 3   then find out the value of    a6+a4+a2+1     a3

Q7.  If  a = 2+ 3   and b = 2 - 3

then find out the value of    a2+b2  a3 + b3    =  ?

Q8. If a+ b + 1 = 0    then find out the value of   a3+b3+1-3ab

Q9. If  x2+3a+1=0  then find out the value of  x3+1x3

Q 10. If xaxbxc=1      then find out the value of   a3+b3+c3

Q 11 . If a+1a+2=0   then find out the value of    a37-1a100

Q 12.If  x3=y2    then find out the value of   2x +3y3x-2y

Q 13. If x+14x=32    then find out the value of  8x3+18x3

Q14. If a-12+b+22+c+12=0  then find out the value of   2a – 3b + 7c

Q 15. Find out the value of  y-z3+z-x3+x-y3

Q 16.if  ab+ba=1 then find out the value of a3+b3

Q 17. If  x2+y2+1x2+1y2=4 then find out the value of x2+y2

Q 18. If x2=y+z  ,  y2=z+x  and z2=x+y

Then find out the value of 1x+1+1y+1+1z+1

Q 19. If  2x=3y=6-z    then find out the value of   1x+1y+1z

Q 20. If  1x+y=1x+1y      then find out the value of   x3-y3

•  12.3

• 970

• 66

• 55

• 395

• 56

• 726

• 56

• -18

• 3abc

• -2

• 12/5

• 18

• 6

• 3(x-y)(y-z)(z-x)

• 0

• 2

• 1

• 0

• 0