9599eba80a4f16a143088a53f69a56f2
2021.31
topperlearning.com
9599eba80a4f16a143088a53f69a56f2
factorise (i) (2a +b) whole square -6a-3b-4 
(ii) a square - (2a+3b) whole square
topperlearning.com
2021.31
(i)
(2a +b)2 - 6a - 3b - 4
= (2a +b)2 - 3(2a + b) - 4
= (2a +b)(2a + b - 3) - 4
= (2a +b)(2a + b - 3) - 4
 
(ii) a2 - (2a + 3b)2
= (a + 2a + 3b)(a - 2a - 3b)
= (3a + 3b)(-a - 3b)
6a2e1aaa2d8eeb21ccd09f302f9963ed
2021.21
topperlearning.com
6a2e1aaa2d8eeb21ccd09f302f9963ed
binomial
topperlearning.com
2021.21
it is known that the number of terms in the expansion of (x1 + x2 + ... +xr)n = n+r-1cr-1.
use this formula to find the number of terms in the expansion of the given expression.
5f7acd9f776abfd14884c8afb9c31e07
2021.17
topperlearning.com
5f7acd9f776abfd14884c8afb9c31e07
please answer
topperlearning.com
2021.17
 
                1    3    5    9
           x   4    5    1    8
           1   0    8    7    2
+         1   3    5    9    x
+     6  7   9    5    x    x
+ 5  4  3   6    x    x    x
   6  1  3   9    9    6    2
  

add70e8891035482e9e6a0033dea12ec
2021.39
topperlearning.com
add70e8891035482e9e6a0033dea12ec
a²-(2a+3b)²


topperlearning.com
2021.39
a2 - (2a + 3b)2 = a2 - [(2a)2 + (3b)2 + 2(2a)(3b)]
= a2 - 4a2 - 9b2 - 12ab
= -9b2 - 12ab - 3a2
d1a47c38dcfbc3005bfcf867b87d3059
2021.10
topperlearning.com
d1a47c38dcfbc3005bfcf867b87d3059
prove
topperlearning.com
2021.10
tan2a - sin2a =tan2a . sin2a


rhs


sin2a/cos2a --sin2a


= sin2a -- sin2a. cos2a  /  cos2a


=sin2a ( 1- cos2a )  / cos2a


=tan2a . sin2a   lhs


 


1+ sin a /1 - sin a =( sec a + tan a)2


rhs


( 1 + sin a) ( 1+ sin a) /  1 -- sin2a


= ( 1 + sin a )2 / cos2a


=1 + sin2a + 2 sina / cos2a


=1/cos2a  +  sin2a /  cos 2a+ 2 sin a/ cos a   .1/cosa


=sec2a  + tan2a  + 2 tan a sec a


= ( sec a + tan a )2


 


 

