Surds and Indices
- Solve the below equation.
173.5 x 177.3 ÷ 174.2 = 17?
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173.5 x 177.3 ÷ 174.2 = 17?
Apply the Laws of Exponents ::
(am) x (an) = am+n
Fractional Exponents ::
am÷ a n=am?n
⇒ 173.5 + 7.3 - 4.2 = 17?Correct Option: C
173.5 x 177.3 ÷ 174.2 = 17?
Apply the Laws of Exponents ::
(am) x (an) = am+n
Fractional Exponents ::
am÷ a n=am?n
⇒ 173.5 + 7.3 - 4.2 = 17?
⇒ 176.6 = 17?
∴ ? = 6.6
- Simplify ( 6a-2bc-3/4ab-3c2 ) ÷ ( 5a-3 b2c-1/3ab-2c3 )
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Given equation is,
( 6a-2bc-3/4ab-3c2 ) ÷ ( 5a-3 b2c-1/3ab-2c3 )
Apply the algebra law a ÷ b = a x 1/b
Apply the law of Fractional Exponents and Laws of Exponents
(am)(an/) = am+n
am÷an=am-n
Or
am/an=am-n
Solve the equation.Correct Option: B
Given equation is,
( 6a-2bc-3/4ab-3c2 ) ÷ ( 5a-3 b2c-1/3ab-2c3 )
Apply the algebra law a ÷ b = a x 1/b
= ( 6a-2bc-3/4ab-3c2 ) x ( 3ab-2c3/5a-3 b2c-1 )
= ( 6a-2 bc-3 x 3ab-2c3) / ( 4ab-3c2 x 5a-3b2c-1 )
Apply the law of Fractional Exponents and Laws of Exponents
(am)(an) = am+n
am÷an=am-n
Or
am/an=am-n
= 18a-2 + 1 b1 - 2 c -3 + 3 / 20a1 - 3 b-3 + 2 c2 - 1
= 9a-1b-1c0/ 10a - 2 b-1c1
= ( 9/10 ) a-1 + 2b-1 + 1 c0 - 1
= ( 9/10 ) a1b0 c-1
= ( 9/10 ) ac-1 [∵ b0 = 1]
- The expression [(√2)√2]√2 gives
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Given expression = [(√2)√2]√2
= (√2)(2)√2/2
Apply the law of algebra formula and solve the equation.Correct Option: D
Given expression = [(√2)√2]√2
= (√2)(2)√2/2
= (√2)(2)1/√2
= (2)1/2 x 21/√2
= 2(2/21/√2)
= (2)(2)(1/√2 - 1)
which denotes a real number but not a rational number .
- If ( 5 + 2√3 ) / ( 7 + 4√3 ) = a + b√3, then the value of a and b is ?
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Given equation is,
( 5 + 2√3 ) / (7 + 4√3 )
Now Multiply and divide by ( 7 - 4√3 ) in above given equation.
By Rationalization, we will get,
[ ( 5 + 2√3 ) / ( 7 + 4√3 ) ] x [ ( 7 - 4√3 ) / ( 7 - 4√3 ) ]
[ ( 5 + 2√3 ) x ( 7 - 4√3 ) ] / [ ( 7 + 4√3 ) x ( 7 - 4√3 ) ]
Apply the formula and multiplication rule of algebra,
( P + Q ) x (R - S ) = P x R - P x S + Q x R - Q x S .................(1)
( a + b ) x ( a - b) = a2 - b2......................................................(2)Correct Option: A
Given equation is,
( 5 + 2√3 ) / (7 + 4√3 )
Now Multiply and divide by ( 7 - 4√3 ) in above given equation.
By Rationalization, we will get,
[ ( 5 + 2√3 ) / ( 7 + 4√3 ) ] x [ ( 7 - 4√3 ) / ( 7 - 4√3 ) ]
[ ( 5 + 2√3 ) x ( 7 - 4√3 ) ] / [ ( 7 + 4√3 ) x ( 7 - 4√3 ) ]
Apply the formula and multiplication rule of algebra,
( P + Q ) x (R - S ) = P x R - P x S + Q x R - Q x S .................(1)
( a + b ) x ( a - b) = a2 - b2.......................................................(2)
= ( 5 x 7 - 5 x 4√3 + 7 x 2√3 - 2√3 x 4√3 )/ ( 72 - (4√3)2 )
= 35 - 20√3 + 14√3 - 8 x 3 / ( 49 - 16 x 3 )
= ( 35 - 24 - 6√3 )/(49 - 48 )
= 11 - 6√3
∵ ( 5 + 2√3 ) /( 7 + 4√3 ) = a + b√3
∴ a + b√3 = 11 - 6√3
on equating the above equation and we get,
or a = 11 and b = - 6
- √5 + ∛x = 3, then the value of x is ?
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√5 + ∛x = 3
Apply the law of Algebra Law.
Square both side of equation and solve the equation.Correct Option: A
√5 + ∛x = 3
Apply the law of Algebra Law.
Square both side of equation.
(√5 + ∛x)2 = 32
⇒ 5 + ∛x = 9
⇒ ∛x = 9 - 5
⇒ ∛x = 4
Now cube the both side of equation,
⇒ ( ∛x ) 3 = 43
⇒ x = (4)3
⇒ x = 64