if a = 2 + ?3, then what is the value of (a² + a ^-2)?

Correct Answer: 1

Explanation:

? = 1/ ( 1 + x^{b - a} + x^{c - a} ) + 1/ ( 1 + x^{a - b} + x^{c - b} ) + 1 / ( 1 + x^{b - c} + x^{a - c} )
Apply the law of algebra and solve the given equation.
? ? =1/ ( 1 + x^b/x^a + x^c/x^a ) + 1/ ( 1+ x^a/x^b + x^c/x^b ) + 1/ ( 1 + x^b/x^c + x^a/x^c )
? ? = x^a/ ( x^a+x^b+x^c ) + x^b/ ( x^b + x^a+ x^c ) + x^c/ ( x^c+x^b+x^a )
? ? = ( x^a + x^b + x^c ) / ( x^a + x^b + x^c ) = 1

Correct Answer: ?3

Explanation:

Let us assume
P = ?1 + a + ?1 - a
Square on both side,
P ² = ( ?1 + a + ?1 - a ) ²
Use the formula ( a + b ) ² = a ² + b ² + 2ab
we will get
? P ² = (1 + a) + (1- a) + 2 ?1 + a x ?1 - a
? P ² = (1 + a) + (1- a) + 2 ?(1 + a ) x ( 1 - a )
? P ² = 2 + 2 ?1 - a²
? P ² = 2 (1 + ?1 - a²)
Now put the value of a which is given in question;
? P ² = 2 (1 + ?1 - ( ?3/2 )²)
? P ² = 2(1 + ?1 - 3/4 )
? P ² = 2(1 + ?1/4 )
? P ² = 2(1 + 1/2) = 2 x 3/2 = 3
? P= ?3
? (?1 + a + ?1 - a) = ?3

Correct Answer: 2

Explanation:

Given equation is below
(p/q)^{n - 1} = (q/p)^{n - 3}
Apply the law of Fractional Exponents and Laws of Exponents
a ^{- m} = 1/a ^m
or
a^m = 1/a ^{- m}
(p/q)^{n - 1} = (q) ^{- (n - 3)} x 1/ (p) ^{- (n - 3)}
(p/q)^{n - 1} = (p) ^{3 - n} x 1/ (q) ^{3 - n}
(p/q)^{n - 1} = (p/q) ^{3 - n}
if p^X = p^Y then X will be equal to Y. means X = Y;
? n - 1 = 3 - n
? 2n = 4
? n = 2

Correct Answer: 0.25

Explanation:

(1/5 )^3a = 0.008 = 8/1000 = 1/125 = (1/5 )³
Apply the Algebra Law and Solve the equation.
? 3a = 3
? a = 1
? ( 0.25 )^a = ( 0.25 )¹ = 0.25

Correct Answer: 47

Explanation:

? = ?103823
? = ?(47) ³
Apply the Law of Algebra
? = [(47)³]^1/3
? = 47^{3 x 1/3} = 47
? = 47

Correct Answer: irrational unless n is the mth power of an integer

Explanation:

If m and n are natural numbers, then m?n is irrational unless n is m^th power of an integer.

Correct Answer: 4

Explanation:

Given that ,
m = 7 - 4?3
Then I/m = 1/7 - 4?3......................(1)

Now multiply and divide with 7 + 4?3 in Eq. (1)
We will get,
1/m = ( 1/7 - 4?3 ) x ( 7 + 4?3 / 7 + 4?3)
?1/m = ( 7 + 4?3 )/ ( 7 - 4?3 ) x ( 7 + 4?3
?1/m = ( 7 + 4?3 ) / ( 7² - ( 4?3)² )
?1/m = ( 7 + 4?3 ) / ( 49 - 4 x 4 x 3 )
?1/m = ( 7 + 4?3 ) /49 - 48
?1/m = ( 7 + 4?3 ) / 1
?1/m = 7 + 4?3
? m + 1/m = 14
? ( m + 1/m ) + 2 = 14 + 2 = 16
? (?m + 1/?m)² = ( m + 1/m )+ 2
? (?m + 1/?m)² = 16
? (?m + 1/?m)² = 4²
? (?m + 1/?m) = 4

Correct Answer: 12

Explanation:

?2ⁿ = 64 ? 2ⁿ = (64)²
? 2ⁿ = (2 × 2 × 2 × 2 × 2 × 2)²
? 2ⁿ = (26)² ? 2ⁿ = 26 × 2 = 212
? n = 12.

Correct Answer: 1

Explanation:

If any given number (suppose x) is a rational number other than zero, then x⁰ = 1.

Correct Answer: 3a b 2 c

Explanation: