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2+3×2+2+3×2+2+2+3×2−2+2+3\sqrt{2+\sqrt{3}} \times \sqrt{2+\sqrt{2+\sqrt{3}}} \times \sqrt{2+\sqrt{2+\sqrt{2+\sqrt{3}}}} \times \sqrt{2-\sqrt{2+\sqrt{2+\sqrt{3}}}} is equal to

Solution

✅ Correct Option: 1

2+3×2+2+3×2+2+2+3×2−2+2+3\sqrt{2+\sqrt{3}} \times \sqrt{2+\sqrt{2+\sqrt{3}}} \times \sqrt{2+\sqrt{2+\sqrt{2+\sqrt{3}}}} \times \sqrt{2-\sqrt{2+\sqrt{2+\sqrt{3}}}}

Let's define:

a=3a = \sqrt{3}

b=2+a=2+3b = \sqrt{2+a} = \sqrt{2+\sqrt{3}}

c=2+b=2+2+3c = \sqrt{2+b} = \sqrt{2+\sqrt{2+\sqrt{3}}}

d=2+c=2+2+2+3d = \sqrt{2+c} = \sqrt{2+\sqrt{2+\sqrt{2+\sqrt{3}}}}

Our expression is then: b×c×d×2−cb \times c \times d \times \sqrt{2-c}

The key insight is that these nested square roots form a pattern where:

b2=2+ab^2 = 2+a

c2=2+bc^2 = 2+b

d2=2+cd^2 = 2+c

From this, we get:

c2−2=bc^2-2 = b

d2−2=cd^2-2 = c

For the term 2−c\sqrt{2-c}, note that:

2−c×d=2−c×2+c=(2−c)(2+c)=4−c2=4−(2+b)=2−b\sqrt{2-c} \times d = \sqrt{2-c} \times \sqrt{2+c} = \sqrt{(2-c)(2+c)} = \sqrt{4-c^2} = \sqrt{4-(2+b)} = \sqrt{2-b}

Similarly:

2−b×c=2−b×2+b=4−b2=4−(2+a)=2−a\sqrt{2-b} \times c = \sqrt{2-b} \times \sqrt{2+b} = \sqrt{4-b^2} = \sqrt{4-(2+a)} = \sqrt{2-a}

And:

2−a×b=2−a×2+a=4−a2=4−3=1=1\sqrt{2-a} \times b = \sqrt{2-a} \times \sqrt{2+a} = \sqrt{4-a^2} = \sqrt{4-3} = \sqrt{1} = 1

Therefore:

b×c×d×2−cb \times c \times d \times \sqrt{2-c}

b×c×2−b=b×1=1b \times c \times \sqrt{2-b} = b \times 1 = 1

b×2−a=1b \times \sqrt{2-a}=1

So the value of the given expression is 11.

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