(2√5+3√5)² simplify Class 9th Maths first chapter
Answers
Answer:
125
Step-by-step explanation:
(2√5+3√5)²
= (2√5)² + 2(2√5)(3√5) + (3√5)²
= 4 x 5 + 12 x 5 + 9 x 5
= 20 + 60 + 45
= 125
Answer:
125
Step-by-step explanation:
ok, so going upon BODMAS (Brackets, Off, Division, Multiplication, Addition, Subtraction), first we will solve brackets first.
Further, within brackets, we come into seeing two operations; multiplication, and addition, out of which BODMAS states, multiplication needs to be done first. But first, let's make things easier by solving the square roots.
Note : The order of operations under the bracket operation don't now depend upon the BODMAS rule, since they after all, do come under the brackets operation, so they, in the course of solving the brackets, also have to be eventually solved. Further, in order to carry out these operations individually, we have to apply BODMAS, as within the brackets, first multiplication, then addition, as stated by BODMAS.
so square root 5=2.2360679775
we can take it up to 3 decimal values, so 2.236.
The equation now seems like this:
(2*2.236+3*2.236)^2 (when there is nothing, as in no operation sign between any two values, we take it as if they are multiplying, to form just one product as we see in the question, composed of them individual numbers)
accordingly, now lets multiply the two;
i) 2(2.236) = 4.472=4.5
equation= (4.5+3*2.236)^2
ii) 3(2.236)= 6.7
equation= (4.5+6.7)^2
Now, adding the two
4.5+6.7=11.2
so the equation seems now something like this:
(11.2)^2
Now, solving the powers (square):
11.2^2= 11.2*11.2= 125.44
Rounding off to 3 sig. fig.= 125
Hence, the answer is= 125.
No offence, but by grade 9, you should be, to the least, knowing basic concepts as these.