Examples: Algebraic Identities(Part 2) Video Lecture - Class 8

hello friends this video on algebraic
expressions part 20 is brought to you by
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question number 4 simplifies 4m + 5 8
whole square plus 5m + 4 + whole square
so again here also you if you look at
this distance of the form a plus B whole
square similarly this term is also of
the form a plus B whole square let us
solve both of these separately and then
add the two so the first part a square
that is 4 M square plus B square that is
5 n square plus 2 a B that is 2 into 4 m
into v n similarly or for this term it
would be a square that is fine and when
I make sure that you do not write again
5m 12 because it is acidified n whole
square this total side n is 8 so a
square will total 5 m square so files in
whole square plus 4 and whole square
plus 2 into 5 m into 4 and let's call
this this would be 16 in 2025 n square
plus 5 to the 10 10 into 4 50 m 40 ml +
25 m square plus 16 n square plus 40 m n
so this becomes equal to 16 M square
plus 25 n square plus 40 M n plus 25 M
square plus 16 L square + 40 + n now
let's rearrange to get the light terms
together so 16 m square + 25 and 27
items to be put them together again 25 n
square + 16 + square right terms we put
them together 40 MN + 40 Ln are also
later so we have grouped them together
add further items so 16 plus 25 would be
41
again 25 plus 16 would be 41 and square
the 40 plus 40 would be HTML so this
would be the result question number five
show that a minus D into a plus B plus B
minus C into D plus B we plus B plus C
minus a into c plus a is equal to zero
so in this case let's simplify the left
hand side that is a minus a into a me
plus a minus B into a plus B this can be
written as a square minus B Square right
similarly the next term is d minus e
into B plus C so this can be written as
d square minus C square and in the third
part is t minus a into c plus 8 this can
be written as C square minus a square so
now if you remove the brackets you can
write it as a square minus B square plus
B square minus C square plus B Square
minus a square so minus B square plus B
square cancel out minus 3 square plus B
Square will cancel out a square minus a
squared cancel out so we will get 0
which is equal to the right hand side
hence little rude question Oh mistake
using identity evaluate 297 into 303 so
how can we make use of identities here
so just try to think of a whole number
which is very close to 297
but which is a rounded number that is a
number with zeroes at the end so a
number that even think of which is close
to do now 2,300
in fact 300 is a number which is also
close to 300 Street so basically we try
to locate a number which is a number
with zeros at the end and which is close
to both the given numbers so how can we
write 297 sir 297 can be written as 300
minus 3 and 303
as 300-plus feet finale you see how
beautiful the desperation is it is in
the form of a minus B into a plus B so
this is equal to a square minus B Square
so this would be ninety thousand minus 9
that is equal to 8 9 9 9 1 using X plus
8 into X plus B is equal to X square
plus a plus B into X plus 85 five point
one two five point two so first let us
see what is that rounded number which is
close to five point one and five point
two so that number is 5 so we can write
five point one and five plus point one
similarly we can write five point two
and five plus point three so when you
look at this these are two binomials
there one doable thing that is filed is
same so this is of the form of X plus a
into X plus B there five is the eight
point one eight and point 2 is B let us
put it in this formula that is x squared
5 squared plus 8 plus B that is 0.1 plus
0.2 eat 2 X that is into 5 plus a into B
that is 0.1 into point 5 into 5 would be
25 point 1 point 2 to point 3 into 5
plus y plus Z 2 point 2 would be point
zero 2 so this would be equal to 25 plus
1 point 5 plus point 0 2 this is equal
to twenty six point five in so this will
be the final value so with this we have
reached two at the end of this lesson
and debris expressions and identities
and I hope that this would have helped
you try to follow moral more expressions
and I'm sure you're going to enjoy it
because this language fun
causing these equations and that will
also help you to gain more expedite
the concept to see you all in the next
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