user64890: I have a address- n3xYQtxvVwpBPSbgGsGRdMWz1YTUjakiMV, amount  that i want to send-1 BTC and i have a private key. How can i create a raw transaction using it and broadcast it to blockchain using bitcoin core.
I have tried this command:
bitcoin-cli createrawtransaction '[{"txid":"dbdc2e2c7f143af70c5e7e8725f55d226b3c058d7bf34a303‌​091b3c6a514848c","vo‌​ut":1}]' '{"n3xYQtxvVwpBPSbgGsGRdMWz1YTUjakiMV":1}' 

and this: bitcoin-cli sendrawtransaction XXX

user59146: You can use signrawtransaction, this method accept an array of private keys as an argument. 
Parameter #3—private keys for signing:

An array holding private keys. If any keys are provided, only they
  will be used to sign the transaction (even if the wallet has other
  matching keys). If this array is empty or not used, and wallet support
  is enabled, keys from the wallet will be used


user38482: EDIT: based on OPs request, I put examples in here:
there are a lot of examples for different tx types on bitcoin.org, in the developer examples. Basically you will need three steps. Assuming you are on OpenBSD/MacOS/Linux, you can go this way:
1.) createrawtransaction - this is what you have already, and it looks ok. I don't know if the previous tx ID or v_out is correct, assuming you know the details, your string is ok (otherwise check with "bitcoin-cli -regtest listunspent", and adopt TX_ID and V_OUT accordingly). I also assume, that the address is one which is in your wallet. Otherwise you might just create an address, and proceed afterwards like this:
UTXO_TXID=dbdc2e2c7f143af70c5e7e8725f55d226b3c058d7bf34a303‌
UTXO_VOUT=1
NEW_ADDRESS=n3xYQtxvVwpBPSbgGsGRdMWz1YTUjakiMV
bitcoin-cli -regtest createrawtransaction '''
    [
      {
        "txid": "'$UTXO_TXID'",
        "vout": '$UTXO_VOUT'
      }
    ]
    ''' '''
    {
      "'$NEW_ADDRESS'": 1
    }'''

you provide this returned hex string to another variable: 
RAW_TX=01000...

2.) signrawtransaction - the previous command returns a hex string, that you will use to sign the transaction - again, see the docs. First I verify my created tx, and then sign: 
bitcoin-cli -regtest decoderawtransaction $RAW_TX
bitcoin-cli -regtest signrawtransaction $RAW_TX

again you assign the result to a variable: 
SIGNED_RAW_TX=01000...

3.) sendrawtransaction - again you take the hexstring of the previous command as parameter, and/or see the docs.
bitcoin-cli -regtest sendrawtransaction $SIGNED_RAW_TX

and maybe a verification as step 4:
bitcoin-cli -regtest generate 1

this generates a block, and you can see on the $NEW_ADDRESS, if funds have been transferred. 
I just entered the two keywords here in the search function, and also found a lot of answers. 

64890: <p>I have a address- <code>n3xYQtxvVwpBPSbgGsGRdMWz1YTUjakiMV</code>, amount  that i want to send-<code>1 BTC</code> and i have a <code>private key</code>. How can i create a raw transaction using it and broadcast it to blockchain using bitcoin core.</p>

<p>I have tried this command:</p>

<pre><code>bitcoin-cli createrawtransaction '[{"txid":"dbdc2e2c7f143af70c5e7e8725f55d226b3c058d7bf34a303‌​091b3c6a514848c","vo‌​ut":1}]' '{"n3xYQtxvVwpBPSbgGsGRdMWz1YTUjakiMV":1}' 
</code></pre>

<p>and this: <code>bitcoin-cli sendrawtransaction XXX</code></p>
 59146: <p>You can use <a href="https://bitcoin.org/en/developer-reference#signrawtransaction" rel="nofollow noreferrer"><code>signrawtransaction</code></a>, this method accept an array of private keys as an argument. </p>

<p>Parameter #3—private keys for signing:</p>

<blockquote>
  <p>An array holding private keys. <em>If any keys are provided, only they
  will be used to sign the transaction (even if the wallet has other
  matching keys).</em> If this array is empty or not used, and wallet support
  is enabled, keys from the wallet will be used</p>
</blockquote>
 38482: <p><strong>EDIT: based on OPs request, I put examples in here:</strong></p>

<p>there are a lot of examples for different tx types on bitcoin.org, in the <a href="https://bitcoin.org/en/developer-examples#simple-spending" rel="nofollow noreferrer">developer examples</a>. Basically you will need three steps. Assuming you are on OpenBSD/MacOS/Linux, you can go this way:</p>

<p><strong>1.) createrawtransaction</strong> - this is what you have already, and it looks ok. I don't know if the previous tx ID or v_out is correct, assuming you know the details, your string is ok (otherwise check with "bitcoin-cli -regtest listunspent", and adopt TX_ID and V_OUT accordingly). I also assume, that the address is one which is in your wallet. Otherwise you might just create an address, and proceed afterwards like this:</p>

<pre><code>UTXO_TXID=dbdc2e2c7f143af70c5e7e8725f55d226b3c058d7bf34a303‌
UTXO_VOUT=1
NEW_ADDRESS=n3xYQtxvVwpBPSbgGsGRdMWz1YTUjakiMV
bitcoin-cli -regtest createrawtransaction '''
    [
      {
        "txid": "'$UTXO_TXID'",
        "vout": '$UTXO_VOUT'
      }
    ]
    ''' '''
    {
      "'$NEW_ADDRESS'": 1
    }'''
</code></pre>

<p>you provide this returned hex string to another variable: </p>

<pre><code>RAW_TX=01000...
</code></pre>

<p><strong>2.) signrawtransaction</strong> - the previous command returns a hex string, that you will use to sign the transaction - again, see the docs. First I verify my created tx, and then sign: </p>

<pre><code>bitcoin-cli -regtest decoderawtransaction $RAW_TX
bitcoin-cli -regtest signrawtransaction $RAW_TX
</code></pre>

<p>again you assign the result to a variable: </p>

<pre><code>SIGNED_RAW_TX=01000...
</code></pre>

<p><strong>3.) sendrawtransaction</strong> - again you take the hexstring of the previous command as parameter, and/or see the docs.</p>

<pre><code>bitcoin-cli -regtest sendrawtransaction $SIGNED_RAW_TX
</code></pre>

<p>and maybe a verification as step 4:</p>

<pre><code>bitcoin-cli -regtest generate 1
</code></pre>

<p>this generates a block, and you can see on the $NEW_ADDRESS, if funds have been transferred. </p>

<p>I just entered the two keywords here in the search function, and also found a lot of answers. </p>
