Algebra
- If x * y = x2 + y2 – xy, then the value of 9 * 11 is
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x * y = x2 + y2 – xy (Given)
⇒ 9 * 11 = 92 + 112 – 9 × 11
= 81 + 121 – 99
= 202 – 99 = 103Correct Option: B
x * y = x2 + y2 – xy (Given)
⇒ 9 * 11 = 92 + 112 – 9 × 11
= 81 + 121 – 99
= 202 – 99 = 103
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then the value of 5A + 3B + 6C + D + 3E isIf 47.2506 = 4A + 7 + 2C + 5 + 6E , B D
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4A + 7 + 2C + 5 + 6E = 47.2506 B D = 40 + 7 + 2 + 5 + 6 10 100 10000
4A = 40 ⇒ A = 107 = 7 ⇒ 7B = 7 = ⇒ B = 1 B 2 C = 2 ⇒ C = 0.1 10 5 = 5 ⇒ D = 100 D 100 6E = 6 ⇒ E = 0.0001 10000
5A + 3B + 6C + D + 3E
= 5 × 10 + 3 × 1 + 6 × 0.1 + 100 + 3 × 0.0001
= 50 + 3 + 0.6 + 100 + 0.0003
= 153.6003Correct Option: C
4A + 7 + 2C + 5 + 6E = 47.2506 B D = 40 + 7 + 2 + 5 + 6 10 100 10000
4A = 40 ⇒ A = 107 = 7 ⇒ 7B = 7 = ⇒ B = 1 B 2 C = 2 ⇒ C = 0.1 10 5 = 5 ⇒ D = 100 D 100 6E = 6 ⇒ E = 0.0001 10000
5A + 3B + 6C + D + 3E
= 5 × 10 + 3 × 1 + 6 × 0.1 + 100 + 3 × 0.0001
= 50 + 3 + 0.6 + 100 + 0.0003
= 153.6003
- Given that 100.48 = x, 100.70 = y, and xz = y2 , then the value of z is close to
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We have,
100.48 = x, 100.70 = y
∴ xz = y2
⇒ (100.48)z = (100.70)2
⇒ 100.48z = 101.4
⇒ 0.48z = 1.4⇒ z = 1.4 = 2.9 0.48 Correct Option: C
We have,
100.48 = x, 100.70 = y
∴ xz = y2
⇒ (100.48)z = (100.70)2
⇒ 100.48z = 101.4
⇒ 0.48z = 1.4⇒ z = 1.4 = 2.9 0.48
- If a ⊗ b = (a × b) + b, then 5 ⊗ 7 equals to
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It is given that
a ⊗ b = (a × b) + b
∴ 5 ⊗ 7 = (5 × 7) + 7 = 35 + 7 = 42Correct Option: C
It is given that
a ⊗ b = (a × b) + b
∴ 5 ⊗ 7 = (5 × 7) + 7 = 35 + 7 = 42
- If 1 < x < 2, then the value of √(x − 1)2 + √(x − 3)2 is
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Since 1 < x < 2, we have
x – 1 > 0 and
x – 3 < 0
or, 3 – x > 0
∴ √(x − 1)2 + √(x − 3)2
= √(x − 1)2 + √(3 − x)2
[∴ (x − 3)2 = (3 – x)2]
= x – 1 + 3 – x = 2Correct Option: B
Since 1 < x < 2, we have
x – 1 > 0 and
x – 3 < 0
or, 3 – x > 0
∴ √(x − 1)2 + √(x − 3)2
= √(x − 1)2 + √(3 − x)2
[∴ (x − 3)2 = (3 – x)2]
= x – 1 + 3 – x = 2