Question

plz give me the option
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Answer 1

Answer:

-6

Step-by-step explanation:

Let us assume the whole value ( √ 42 + √42 + √ 42 +........ infinite ) as ' x '

X = √ 42 + √42 +√42 + ......

important :-

If x = √ a + √ a + ....

then then values √a + ( √a + √a + .... ) will also be x

Then

x = √ 42 + x

x^2 = 42+x

x^2 - 42 -x = 0

a = 1 , b= -42 , c = -1

x = -b ±√ b^2 - 4ac /2a

x = 42 ± √ 1764 - 4(1)(-1) / 2( 1)

x = 42 ± √ 1768 / 2

x = 1± √ 1+ 4(42) / 2

x = 1± √ 169 /2

x = 1 ± 13 / 2

( + )

x = 14/2 = 7

(-)

x = -12/2 = -6

FØLLØW MÉ