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### Formative Assessment_MCQ

**Question No. 1**

In the given problem, we have to find the value of

Given

We shall use the identity

Here put,

Hence the value of is

Hence the correct choice is (c).

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### Formative Assessment_MCQ

**Question No. 2**

In the given problem, we have to find the value of

Given

We shall use the identity

Here putting,

Hence the value of is

Hence the correct choice is (d).

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### Formative Assessment_MCQ

**Question No. 3**

In the given problem, we have to find the value of

Given

We shall use the identity

Here put,

Squaring on both sides we get,

Hence the value of is

Hence the correct choice is (b).

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### Formative Assessment_MCQ

**Question No. 4**

In the given problem, we have to find the value of

Given

We shall use the identityand

Here put,

Take Cube on both sides we get,

Hence the value of is

Hence the correct choice is (d).

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### Formative Assessment_MCQ

**Question No. 5**

In the given problem, we have to find the value of

Given

We shall use the identity

Here put,

We shall use the identitywe get,

Taking square root on both sides we get,

Hence the value of is

Hence the correct choice is (c).

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### Formative Assessment_MCQ

**Question No. 6**

In the given problem, we have to find the value of

Given

We shall use the identity

Here putting,

Hence the value of is

Hence the correct choice is (b).

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### Formative Assessment_MCQ

**Question No. 7**

In the given problem, we have to find the value of

Given

We shall use the identity

Put we get,

Substitute y = 5 in the above equation we get

The Equation satisfy the condition that

Hence the value of is 5

The correct choice is (a).

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### Formative Assessment_MCQ

**Question No. 8**

In the given problem, we have to find the value of

Given

We shall use the identity

Put we get,

Substitute *y* = 2 in above equation we get,

The Equation satisfy the condition that

Hence the value of is 2

Hence the correct choice is (d).

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### Formative Assessment_MCQ

**Question No. 9**

The correct choice is (b).

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### Formative Assessment_MCQ

**Question No. 10**

In the given problem, we have to find the value of

Hence the correct choice is (b).

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### Formative Assessment_MCQ

**Question No. 11**

By transposing left hand side we get,

The correct choice is (b)

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### Formative Assessment_MCQ

**Question No. 12**

Multiplying both sides by 2 we get,

Therefore the sum of positive quantities is zero if and only if each quantity is zero.

The correct choice is (d).

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### Formative Assessment_MCQ

**Question No. 13**

The correct choice is (d).

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### Formative Assessment_MCQ

**Question No. 14**

Taking Cube on both sides we get,

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### Formative Assessment_MCQ

**Question No. 15**

By transposing +46 to left hand side we get,

The correct choice is (a).

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### Formative Assessment_MCQ

**Question No. 16**

By transposing +46 to left hand side we get,

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### Formative Assessment_MCQ

**Question No. 17**

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### Formative Assessment_MCQ

**Question No. 18**

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### Formative Assessment_MCQ

**Question No. 19**

We have to find the product of

Using identity

We can rearrange as

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### Formative Assessment_MCQ

**Question No. 20**

Taking Least common multiple in we get,

The correct choice is (d).

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### Formative Assessment_MCQ

**Question No. 21**

We have to find the product of

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### Formative Assessment_MCQ

**Question No. 22**

Transposing -288 to left hand side we get

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### Formative Assessment_MCQ

**Question No. 23**

We have to find the possible dimension of cuboid

Take 3 as common factor

We get,

Here the dimension of cuboid s’ is 3,

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### Formative Assessment_MCQ

**Question No. 24**

The correct choice is (d).

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### Formative Assessment_MCQ

**Question No. 25**

We have to find the product of

Hence the product of is 10,000

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### Formative Assessment_MCQ

**Question No. 26**

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### Formative Assessment_MCQ

**Question No. 27**

We have to find the value of *b*

We get

Equating ‘*b*’ on both sides we get

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### Exercise : 4.1

**Question No. 1**

In the given problem, we have to evaluate expressions by using identities.

By applying identity we get

(ii) We have been given

We shall use the identity

Here,,

By applying identity we get

Hence the value ofis

(iii) The given expression is

We shall use the identity

Here

By applying identity we get

Hence the value of is

(iv) The given expression is

We shall use the identity

Here

By applying identity we get

Hence the value ofis

(v) The given expression is

We shall use the identity

Here

By applying identity we get

Hence the value ofis

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### Exercise : 4.1

**Question No. 2**

In the given problem, we have to evaluate expressions by using identities.

(i) Given

We can write as

We shall use the Identity

Where ,

By applying in identity we get

Hence the value of is

(ii) We have been given

We can write as

We shall use the identity

Where,

By applying in identity we get

Hence the value of is

(iii) The given expression is

We have

So we can express and in the terms of as

We shall use the identity

Here

By applying in identity we get

Hence the value of is

(iv) The given expression is

We have

So we can express and in the terms of 100 as

We shall use the identity

Here

By applying in identity we get

Hence the value of is