Wall Street inches higher at open on M&A lift

Big M&A deals boosted market optimism a day after the S&P 500's worst performance in a month

US stocks inched up at the open on Tuesday as a pair of big M&A deals boosted market optimism a day after the S&P 500's worst performance in a month.

The Dow Jones industrial average rose 24.71 points, or 0.14 percent, to 17,801.51, the S&P 500 gained 2.03 points, or 0.1 percent, to 2,055.47 and the Nasdaq Composite added 8.86 points, or 0.19 percent, to 4,736.20.